Last season, the Chicago Cubs were in need of bullpen help, so they traded for closer Aroldis Chapman at the deadline and went on to win the World Series. This season, they've acquired another lefty who can rack up strikeouts in Justin Wilson and a capable catcher in Alex Avila.

Wilson is striking out 12.3 batters per nine innings this season, fifth among left-handed relievers with at least 20 appearances. The only players in that group with a better rate? Aroldis Chapman (13.0), Andrew Miller (13.0), Sean Doolittle (12.7) and Jerry Blevins (12.4).

Wilson’s 2.68 ERA is on pace to be his best since he posted a 2.08 ERA with the Pirates in 2013, and his 0.94 WHIP is on pace to be the best of his career. His acquisition strengthens the back end of the Cubs' bullpen, giving the team five relievers with sub-3.00 ERAs this season.

The Cubs have also needed a backup catcher since they traded Miguel Montero on July 3. Avila has the second-highest OPS (.869) among catchers with at least 250 plate appearances this season, trailing only Buster Posey. His OPS this season is more than 100 points higher than it was in any of his previous five seasons in the majors.

The Cubs' newest catcher also ranks seventh in batting average (.274) and ninth in slugging percentage (.475) among that group.

These improvements have come at a price, however.

With Jeimer Candelario reportedly going to Detroit, five of the Cubs' top-seven prospects in Keith Law's rankings heading into this season (1. Eloy Jiménez, 2. Ian Happ, 3. Dylan Cease, 4. Albert Almora, Jr. and 7. Jeimer Candelario) have either graduated the farm system or been traded.