Make no mistake, Matt Maloney is a good pitcher. He's got talent and will likely wind up as a serviceable Major League pitcher, but isn't likely to be a dominant pitcher in the majors. He's likely a mid-rotation type guy and the Phillies could afford to give him up since they have other, more highly touted pitchers to cover his loss.
As for Kyle Lohse, he's a pitcher who looked pretty solid after posting a 13-8, 4.23 mark for the 2002 Minnesota Twins. That was Lohse's second season in the majors and he followed it with a 14 win season, but his ERA did jump to 4.61 in 2003 and he also lost 11 games. After scuffling in 2004, he gave his best effort the following season when he threw a career-low ERA of 4.18, but was just 9-13 on a Twins team that went 83-79. After a tough start to 2006, he was sent packing to the Cincinnati Reds and has been there ever since.
As a National Leaguer, Lohse has gone 9-17 and has a 4.58 ERA in 32 starts for Cincinnati. His ERA is slightly better than his 4.83 over all ERA posted over six plus seasons. His career ERA is just over the average for his time in the Majors.
The bottom line on Lohse is that he's generally a pretty steady pitcher, but has never reached the potential that a lot of people predicted for him earlier in his career. If you take his career stats and average them out to project an average season for Lohse, he would throw 192.3 innings, which is one factor that the Phillies like about Lohse in that he will generally keep you in games. Over those 192 innings, he would average giving up 26 home runs or 1.2 every nine innings. He averages just under three walks per nine innings and just under six strikeouts per nine innings, both decent numbers.
The question is whether Kyle Lohse is better than what the Phillies already have in their rotation.
The Phillies haven't made it official, but it's likely that Lohse will replace J.D. Durbin in the starting five. While Durbin wasn't dominating in his last start, he has thrown a complete game shutout this season and has a 4.30 ERA as a Phillie this season, which is a better mark than Lohse's mark with the Reds, although in a much smaller sampling. Lohse gave Cincinnati nearly 6.3 innings of work per start this year, while Durbin has been just slightly under that number. The big edge comes in control, where Lohse has shown much better walk ratio numbers than Durbin whether you take Lohse's career numbers or his numbers this season with Cincinnati. Durbin's home runs per nine innings numbers are better than Lohse's, but not when you look at Durbin's numbers at Citizens Bank Park, where Durbin has surrendered all three of his home runs this season. In fact, Durbin has struggled mightily at home this year, although his recent resurgence came on a road trip where he threw two strong games in Los Angeles and San Diego.
Lohse's veteran status and the fact that he's pitched in pennant races and in post-season, probably give him a slight edge over Durbin, but likely not much. There is no telling how good Durbin might have become if he was allowed to continue pitching out of the Phillies' starting rotation.
Another option would be to move Adam Eaton to the bullpen and put Lohse into his spot in the rotation. It may be interesting to see if the Phillies consider that should Eaton struggle Tuesday night in Chicago. While Eaton's career numbers suggest that he's the better pitcher, Lohse's season numbers give him a distinct advantage in the here and now. The Phillies considered having Eaton start the season in the bullpen and could consider it again if he continues to stumble. It will be interesting to see how Eaton pitches in Chicago and if the Phillies will react should he be shelled.
Lohse is a decent pick-up. There may not have been a better starter out there for the Phillies to pursue and they didn't give up a monster prospect to get him, so the deal makes sense. Even if Lohse leaves as a free agent after the season, losing Maloney isn't likely to come back and bite them in the end; at least not bite them too hard. It would have been nice to get a higher profile starter, but history will probably show that there won't be big name starters changing addresses at this year's trading deadline. If there are bigger names that move around, then the Phillies might have missed the boat on some potential deals.