Bill Monbouquette grew up in a tough neighborhood in West Medford, Massachusetts, and he had a bulldog demeanor as a ballplayer. Both parents were Boston natives. Bill was born on August 11, 1936, and he went to Medford High School. He was throwing from an early age. He was a Boston Braves fan in his youth, though.

He played cadet and midget ball, American Legion ball, and then high school baseball. He also played semipro ball for the Red Birds of neighboring Everett, Massachusetts. Pitching in high school for the Medford Mustangs, he first made the Boston newspapers in the spring of 1953, when the paper noted him throwing a two-hitter with 12 strikeouts in a game against Quincy. Monbouquette also played on the high school hockey and soccer teams, but eschewed football. He also played for the St. Raphael amateur team.

In August 1954, he represented New England as starting pitcher in the annual Hearst Sandlot Classic at the Polo Grounds in New York on his 18th birthday. He pitched the first two innings and struck out five of the six batters he faced. He was the unanimous choice as the MVP. In his senior year, he pitched in 17 of Medford's 23 games, was 10-4, and played center field when he wasn't pitching, batting .375. His high school record was 20-8, and on June 20, 1955, he signed with the Red Sox, the signing credited to Sox scout Freddie Maguire.

He was 5-feet-11, weighed 190 pounds, and a right-hander—though, oddly, he wrote and performed all other functions left-handed. Monbouquette, whose nickname was originally "Farmer," was assigned to the Appalachian League (Class D) to pitch for the Bluefield, West Virginia Blue-Grays, the Red Sox farm team there. He was 2-4, but had a 3.06 earned run average and made a good showing. His first full season was for Corning, also in Class D, with a 15-7 record and a 2.45 ERA.

The Greensboro Patriots (Class B) were his team in 1957; he was 11-6 (3.77). He also had the opportunity to pitch 32 innings in six games for Class-A Albany. He was 1-1 with a 5.57 ERA. In 1958, his last year in the minor leagues, he pitched in Triple A for the Minneapolis Millers. He was 8-9, but finished with a strong 3.16 ERA. He was brought up to Boston in mid-July.

Monbouquette was only 21 years old when he got his first start on July 18. He pitched five innings against the visiting Detroit Tigers. He gave up five runs, three earned, and left with the game tied, 5-5. Billy Martin had stolen home on him in the very first inning; teammate Frank Malzone won the 11-9 game in the seventh with a grand slam. Red Sox pitching coach Boo Ferriss was pleased that, even with the pressure of pitching in his hometown, he only walked one batter in his debut—the first man he faced.

His first two decisions were losses, but they were close games—a 3-1 loss on July 23 at Kansas City (only one run was earned) and a 3-2 loss in Detroit on July 31. On August 5 at Fenway, he got his first win, a complete-game 7-1 decision over Washington. By the end of the season, he had pitched in ten games and was 3-4 with a 3.31 ERA, second-best on the team.

Near the end of the season, he entered the United States Army and served in the 182nd Medical Unit at Camp Curtis in Massachusetts from September 21 into July 1959, though he was able to appear in games throughout. Monbouquette was 7-7 that year with a 4.15 ERA.

The Red Sox finished in seventh place in 1960, 32 games behind the first-place Yankees. Monbouquette led the team with 14 wins, four more than anyone else. His standout game was a 4-0 one-hitter on May 7. He also pitched in the All-Star Game that year, starting the first of the two games that year. He'd shut out the league-leading Yankees in his last start, but he was shelled in the All-Star Game, giving up four runs in the first two innings and bearing the loss. He was also named to the squad in 1962 and 1963, but pitched in neither.

He won 14 games again in 1961, just one behind Don Schwall, this time his best game a 17-strikeout win over Washington on May 21. It set a Red Sox team record at the time, topping the 15 struck out by Smoky Joe Wood back in 1911, and set a night-game record in the American League. President Dwight Eisenhower, who'd attended the game, beckoned him over to shake hands. He came within one K of matching the major-league record at the time, and indeed would have had 18 if Jim Pagliaroni had not dropped a fouled third strike in the eighth. He finished 14-14, but six of his losses were one-run games, four of them before the end of May.

The Sox finished dead last in 1962, but Monbouquette won 15 and threw a no-hitter against the White Sox on August 1. A tight 1-0 game, Boston scored its one run in the eighth inning off Early Wynn. He admitted to having been nervous. “I can remember standing on the rubber in the eighth inning—I was really shaking." At the time, he said, "That was the biggest thrill I ever had. That was something very special because I hadn't won a game in close to two months. I was struggling." He'd lost three of four starts in July. "I had Aparicio 0 and 2 and threw him a slider off the plate. He tried to hold up, and I thought he went all the way. The umpire, Bill McKinley, called it a ball, and as I was getting the ball back from the catcher, someone shouted from the stands, ‘They shot the wrong McKinley.’ I had to back off the mound because I had a little chuckle to myself.

“The next pitch, I threw him another slider and he swung and missed." When the team arrived home, "the city sent fire engines, lights flashing, to meet the plane at Logan Airport and give him a parade ride home."

Monbo's best year in some regards was 1963, playing under first-year manager Johnny Pesky. The Sox finished in seventh place (76-85), and yet his record was 20-10, fourth in the league in wins, with a 3.81 ERA. The Yankees finished first for the fourth year in a row. He was a "Yankee killer" that year, beating them four times in five starts. On the downside, he led the league in base hits allowed (258) and earned runs allowed (113).

The '64 Sox finished eighth. Reliever Dick Radatz won a surprising 16 games, but Monbouquette was first among the relievers (despite a losing 13-14 record), with a 4.04 ERA. He again allowed precisely 258 base hits, again leading the league. The old Red Sox record for gopher balls was 31, set by Gene Conley in 1961. Monbo would have set the new record, giving up 34 homers, except that Earl Wilson gave up 37. One of the homers cost him a tough 2-1 loss to the Twins on September 6. It was a complete game one-hitter, but the one hit was a homer in the bottom of the sixth by Zoilo Versalles after Rich Rollins had reached on an error.

In 1965, his 18 losses were the most in the league (10-18, despite an improved 3.70). The Sox slipped another notch down the ladder, to ninth place. In October, the Red Sox traded Monbouquette to the Detroit Tigers, getting three players in return: George Smith, George Thomas, and (more than a year later) Jackie Moore.

Bill Monbouquette pitched in 1966 for the Tigers and two games in 1967. He was 7-8, all in 1966, working 16 games in relief and starting just 14. He did win his 100th major-league game during the season. Understandably, there had been a lot of negative reaction from fandom and pundits in New England, but by the end of the 1966 season, many felt the Sox had made a good trade.

Before the 1967 season began, the Tigers said he would work out of the bullpen. And there was almost none of that—he threw one inning on April 16 and one on the 22nd. He didn't give up any runs in either outing, but the Tigers asked him to report to the minors, to Toledo, and he refused, so they placed him on waivers and then gave him his unconditional release on May 10. He reached out to almost every big-league team, but no one was interested at first. He wasn't ready to retire to the rug and drapery business he had in Massachusetts. After all, he was only 31 years old. Finally, the New York Yankees gave him a chance to make the team and he pitched for them in a May 26 exhibition game against Syracuse. He signed as a free agent with them on the 31st, replacing Jim Bouton on the staff. In 1968, the Yankees gave Monbouquette the opportunity to work as a starter again. The Yankees traded him on July 12 to the San Francisco Giants for another veteran right-hander, closer Lindy McDaniel. The Giants didn't use him much at all. He pitched 12 innings in seven games (giving up four homers in the dozen innings) and was 0-1. On December 21, the Giants assigned him to the Houston Astros on a conditional basis. He pitched in spring training for Houston, but didn't make the team and had to start looking for a job.

On April 9, the Yankees gave him a position as a scout and as a minor-league manager, working for their Appalachian League (rookie league) team, the 1969 Johnson City Yankees.

He pitched 78 complete games, finishing his career with a 114-112 record (3.68). Looking back on his career, he still held himself to a higher standard: "I should have been a better pitcher. I look back at games I should have won and didn't because I made a stupid mistake—usually the mistake of trying to pitch too fine. Sometimes you try to nibble the corners—guiding the ball instead of throwing it. That's wrong; you should be going with your strength." He acknowledged that Fenway Park was a tough place to pitch, with its short left field and the lack of foul territory. "Overall, though, I believe Fenway makes you a better pitcher. You think more, you concentrate more."

In January 1976, he was named manager of the New York Mets' Single-A Midwest League club at Wausau, Wisconsin. That December, he became the Mets' minor-league pitching instructor. During the offseasons, he was in the retail liquor business.

Monbouquette also served two stints as major-league pitching coach for the New York Mets in 1982 and 1983, and (after a stretch working for the Yankees at Fort Lauderdale) for the Yankees in 1985 and ’86. He worked for the Yankees at Albany, too.

He worked teaching pitching at the minor-league level, working for the Toronto Blue Jays in their system—at Myrtle Beach in 1988, for instance. He was recognized with World Series rings in 1992 and 1993, and then worked from 2000 through 2005 as pitching coach for the Oneonta Tigers, Detroit's Single-A team in the New York-Penn League. At the end of the 2005 season, he announced his retirement.

In 2000, he was named to the Red Sox Hall of Fame. After the Red Sox won the World Series in 2004, they were very generous in the number of rings they gave out. One of them went to Bill Monbouquette.

As a Red Sox player, he was a regular supporter of the Jimmy Fund and frequently visited young children receiving cancer treatment, originally at the urging of teammate Ted Williams. When his battle with leukemia began in 2007, Monbouquette was treated at the Dana-Farber Cancer Institute, which saved his life with a stem cell transplant in 2008. He battled leukemia for more than seven years, but ultimately died in Boston on January 25, 2015, from complications of the disease.