It is understandable that any team with postseason aspirations would be interested in acquiring the best pitchers they could. The Chicago Cubs, as the defending World Series champions, are certainly in that group of teams that would be interested in a top of the rotation starter. Add in the struggles of their pitching staff this season, and an upgrade would make sense.
Meanwhile, the Tampa Bay Rays have one of the better starters in the league in Chris Archer. He has had a solid start to the season, as his 5-4 record and 3.75 ERA do not tell the full story.