Selected in the third round of the 1982 free agent draft out of Clemson, the left-handed Key was first used in a relieving role for the Toronto Blue Jays. Jimmy happily moved into the starting rotation his second year in the majors and became one of the top southpaws in the American League in the ’80’s and early ’90’s.
Before Key debuted with the Blue Jays in 1984, the franchise had never enjoyed good left-handed pitching. He broke that trend by setting a club rookie record for saves (10), as well as a club mark for appearances with 63. When Toronto acquired reliever Gary Lavelle in the offseason, Key emigrated from the pen to become the first lefty starter to win a game for Toronto since 1980 — an incredible 614-game dry spell. He went 14-6 while notching a 3.00 ERA, fourth in the league behind his teammate Dave Stieb.
Key’s 2.76 ERA in 1987 was led the league, and his 17 wins tied a club record. Though pained by elbow bone chips in 1988, Key persevered and posted a 12-5 record with a 3.29 ERA. Key continued to give the Jays much-needed quality outings, and was considered a go-to man despite being just a couple of games over .500 each year. Key helped the team reach and win their first World Series victory in 1992, recording two of the four wins in the Fall Classic that year.
Key fled to the New York Yankees in the offseason, and quickly established himself as their ace, going 18-6 and rekindling hopes in the Bombers’ quest for postseason play. The following year Jimmy notched the most wins in the league, going 17-4 by the time the strike broke. But old arm injuries came back to haunt him the next year. After pitching in pain for two straight starts, Key went on the disabled list in May 1995 for a recurrence of tendinitis, but found the injury to be much more serious. Two months later, he underwent season-ending rotator cuff surgery.
Key came back strong the following year, allowing just one earned run in 13 spring training innings, drawing the admiration of his teammates who weren’t sure he could pitch at all, let alone effectively. Ultimately, he couldn’t. His arm injuries had not abated and Key went on the DL twice during the season as the Yankees won their first championship since 1978. It was clear that Key was not the pitcher he once was, sporting a 12-11 record with a 4.68 ERA, the highest ever in a full season for him.
Upset with the Yankees’ low-ball one-year contract offer in December 1996, Key signed on with the Baltimore Orioles, reuniting with former Blue Jay GM Pat Gillick. Jimmy pitched a full 1997 with the O’s, helping to boost yet another team into the postseason.
But when recurring arm injuries and advancing age made him considerably less effective the following year, Baltimore replaced Key in the starting rotation with Juan Guzman, and the lefty headed to the bullpen. By the end of the season, injuries had impaired him to the point that he would require shoulder surgery to be able to pitch again. At the age of 37, Key decided it wasn’t worth it and retired in February 1999 with a .614 lifetime winning percentage.