In 1929, uniform numbers appeared on the back of baseball jerseys for the first time, thanks to the Indians and the Yankees.  By 1937, numbers finally appeared across all uniforms, both home and away, across both major leagues.  Since that time, 81 distinct numbers have been worn by members of the White Sox, while the Cubs boast 76.

Today, we continue our look at those players, picking our favorite, if not the best, player to wear each uniform number for both Chicago teams with #40.  55 different players have donned #40 while playing in Chicago, 25 for the White Sox and 30 for the Cubs.

Acquired in mid-June, along with George Frazier and Ron Hassey, from the Indians in exchange for Mel Hall, Joe Carter, Don Schulze, and Darryl Banks, Rick Sutcliffe, wearing #40, quickly became the ace of the Cubs staff, going 16-1 with a 2.69 ERA in leading the Cubs to their first division title and his first Cy Young Award.  He then homered in and won Game 1 of the NLCS, the first post-season game at Wrigley Field since the 1945 World Series, before dropping the deciding Game 5 in San Diego.  A free agent after the season, Sutcliffe signed a long term deal with the Cubs.

A hamstring injury limited him to 20 starts in 1985, while arm injuries in 1986 led him to a 5-14 record with a 4.64 ERA in 28 appearances.  He bounced back in 1987, leading the league with 18 wins in 34 starts for the last place Cubs, finishing second in the Cy Young Award voting.  He went 13-14 in 1988, but did somehow manage a steal of home plate on July 29th in a victory against the Phillies.  A resurgence in 1989 helped lead the Cubs to their second divisional title, and he made one start against the Giants in the NLCS.  Recurring arm injuries caused Sutcliffe to miss most of the 1990 and 1991 seasons, with only 24 appearances between the two years, and the Cubs let him leave as a free agent following the 1991 season.

On the other side of town, Wilson Alvarez was acquired by the White Sox, along with Scott Fletcher and Sammy Sosa, for Harold Baines and Fred Manrique on July 29, 1989, making his White Sox debut on August 11, 1991 by throwing an unlikely no hitter against the Orioles at Memorial Stadium.  He made 8 additional starts for the White Sox down the stretch, finishing the year with a 3-2 record and a respectable 3.51 ERA.  1992 saw Alvarez work mostly out of the bullpen, getting only 9 starts out of his 34 appearances.  He posted a career high 1.674 WHIP, giving up 65 walks in just over 100 innings.  This led to an unfortunate 5.20 ERA, despite a 5-3 record.  In 1993, Alvarez managed to break in to the rotation full time.  Despite leading the league with 122 walks, he finished second in the AL with an ERA of 2.95 and ended up with a 15-8 record as the White Sox won the AL West title for the first time in a decade.  He was the winning pitcher in Game 3 of the ALCS, holding the Blue Jays to a single run while throwing a complete game.

Alvarez improved in 1994, earning his first (and only) All Star nod and cutting his walk total nearly in half, helped by the player strike that ended the season in August, and he finished the year with a 12-8 record and a 3.45 ERA.  When baseball returned in 1995, Alvarez struggled to regain his groove, finishing with a losing record for the first time and an ERA of 4.32.  1996 saw a nice bounce back for Alvarez.  While his ERA was still an elevated 4.22, he tied his career high with 15 wins and set career highs for innings pitched and strikeouts.  He continued to impress in 1997, putting up a 9-8 record with a 3.03 ERA by the end of July, when, with the White Sox a mere 3 games back in the standings, he, along with Danny Darwin and Roberto Hernandez, was sent to the Giants for Brian Manning, Lorenzo Barceló, Mike Caruso, Keith Foulke, Bob Howry, and Ken Vining in what would become known as the White Flag Trade.