The Cubs won the NL pennant in 1929, but lost the World Series. Team owner William Wrigley badly wanted to get back to the Series, and the Cubs led the NL by four games Sept. 6 after defeating the Pirates 19-14 (!).
Nineteen games remained. The Cubs went 10-9, which isn't terrible... but the Cardinals went 17-4 over that time span and won the pennant by two games.
Wrigley was so angry that he fired manager Joe McCarthy with four games left in the season and replaced him with Rogers Hornsby. The Cubs won all four of those games, but it didn't matter.
McCarthy would go on to win eight pennants and seven World Series with the Yankees. Hornsby was so disliked he had to be fired less than two years later.
Would McCarthy have had that much success had he remained with the Cubs? Impossible to know, but... he did really, really well in New York. This firing was one of the biggest mistakes in franchise history.
We'll grade that "swap" with a big, fat F.
Here are the rest of the significant transactions for the Cubs in 1930.
Moss had pitched in 12 games for the Cubs with a 6.27 ERA. He never pitched in the majors again.
Kelly, near the end of a career spent mostly with the Giants where he'd led the NL in RBI twice, in home runs once and received MVP votes three times, batted .331/.362/.434 in 39 games with the Cubs, but he was 34 years old and nearly done. The Cubs released him the following February.
The PTBNL was Charles Tolson, who'd gone 6-for-20 (.300) in 13 games for the Cubs in '30. He never played in the majors again.
A small positive for this one.
Petty had some good years for the Dodgers in the mid-1920s, but by '30 he was 35 and pretty much done. He pitched all right for the Cubs, a 2.97 ERA in nine games (three starts), but they sent him to the minors the following year and he never played in the majors again.
Sweetland has an odd distinction in MLB history.
In 1930, as you likely know, the ball was unintentionally "juiced" and offenses went crazy. The likely culprit was the seams being too "flat" and pitchers thus were not able to get their usual break on pitches. The Phillies allowed 1,024 runs -- 231 more than anyone else in the NL. It should be no surprise to you that they lost 102 games.
Sweetland was the worst of their staff. From 1927-29 he'd posted a 5.81 ERA for some bad Phillies teams but that exploded to a 7.71 ERA in 167 innings in 1930. That is the highest ERA in MLB history for anyone who threw at least that many innings in a season.And Sweetland started 1930 by throwing a complete-game shutout against the Dodgers! After that his ERA was 8.16.
What did the Cubs see in him? ¯\_(ツ)_/¯
Anyway, Sweetland posted a 5.04 ERA in 26 games (14 starts) for the Cubs in 1931, the best ERA of his career, even though he, like many, did not get along with Hornsby, per Sweetland's SABR biography:
Taciturn, reflective, and typically in control of his emotions, Sweetland chafed under Hornsby's aggressive and confrontational style of managing. After a brutal outing against Brooklyn on June 18 (nine hits and seven runs in 4⅓ innings), Sweetland lost both his spot in the rotation and Hornsby's confidence, and pitched just seven times (two starts) over the next seven weeks. Given a start on August 4, Sweetland tossed a complete game to defeat the Cincinnati Reds in what proved to be his final big-league victory. He started three more games for the Cubs in August, completed two of them, but was plagued by wildness (he issued a career-high ten walks against the Pirates on August 10) and lost each start. With an increasingly acrimonious relationship with Hornsby, Sweetland made just four relief appearances in mop-up situations in September.
After he had a 6.28 ERA in 28 games for their minor league club at Los Angeles in 1932, the Cubs released him.
These are not big names in Cubs history, though Smith had a pretty good year in 1931 (15-12, 3.22 ERA, 3.8 bWAR). He did not repeat that in 1932 and the Cubs included him in the Babe Herman deal after the season. Smith did throw one inning in the 1932 World Series.
Welsh never played for the Cubs, instead playing four years in the minor leagues.
McAfee pitched one year in Boston with a 6.37 ERA in 18 games and was eventually claimed by Washington on waivers. Schulmerich, who had never played for the Cubs, hit .278/.331/.417 in 243 games for the Braves from 1931-33.
Slight edge to the Cubs here.
As was the case for many other deals like this in the Depression era, a MLB team with money helped out a minor-league club. The L.A. team was mainly independent in those years, but did have a working agreement with the Cubs as well.
Baecht posted a 3.71 ERA in 23 games for the Cubs in 1931 and 1932, nothing special. Shealy never played in the majors after 1930 and the others had some brief MLB time after this deal. The Cubs eventually sent Vince Barton and the aforementioned Mal Moss to Los Angeles to complete the deal, though both players essentially stayed affiliated with the Cubs, as Barton played in the majors for them in both 1931 and 1932, and Barton, having just returned from Double-A, was one of the nine Cubs to be the first to wear a uniform number, June 30, 1932 against the Reds at Wrigley Field.
We'll give these a "D" because of the firing of McCarthy.