The Philadelphia Phillies upgraded their rotation at the 2023 MLB trade deadline by acquiring Michael Lorenzen from the Detroit Tigers. The Phillies sent minor-league prospect Hao-Yu Lee to the Tigers. Far from the biggest move on the day of the deadline, the Michael Lorenzen trade was a notable deal.

The Phillies' trade deadline included a pair of moves. In addition to acquiring Lorenzen, Philadelphia swapped pitcher Bailey Falter for Pittsburgh Pirates infielder Rodolfo Castro. The Tigers tried to trade two starters at the deadline. Detroit agreed to send Eduardo Rodriguez to the Los Angeles Dodgers, but the veteran vetoed the deal.

Philadelphia is hoping that Lorenzen helps the team make a second straight surprising run to the World Series. Detroit boosted its farm system, seemingly trapped in an endless rebuild. How did each team fair in the trade?

Let's grade the Michael Lorenzen trade for both the Phillies and Tigers.

Phillies Michael Lorenzen trade grade

The Phillies might be best described as “cautious buyers” at the 2023 trade deadline. Philadelphia surrendered its No. 5 prospect, according to, for a slightly above-average pitcher. It was probably the right strategy, considering their needs and place in the standings.

Philadelphia is in the thick of the NL wild-card race. One day after the trade deadline, the Phillies are second in the wild-card standings, trailing the San Francisco Giants by a half-game for the top spot. The Milwaukee Brewers, Miami Marlins and Arizona Diamondbacks are all within a game of Philadelphia. The Phillies' rotation has a 4.12 ERA, good for fifth in the NL.

Lorenzen's 3.58 ERA is better than that of all four Phillies' pitchers who have made at least 15 starts. Aaron Nola and Zack Wheeler would be Philadelphia's top two starters in a playoff series. Lorenzen could compete with Taijuan Walker, Ranger Suarez and Cristopher Sanchez for a backend rotation spot if the Phillies get back to the playoffs.

In each of the past three seasons, Lorenzen finished with an ERA north of 4.23. A 1.14 ERA from Lorenzen in June allowed the Tigers to raise their asking price for the starter. Lorenzen is also a rental, adding some more risk to the trade from a Phillies' perspective.

Phillies Trade Grade: B-

Tigers Michael Lorenzen trade grade

The Tigers probably didn't think they were getting a team's No. 5 prospect in exchange for Lorenzen one month ago when the veteran had a 4.28 ERA. It's a solid return for a pitcher who was struggling at the end of June and is headed for free agency. Lorenzen was named to his first All-Star team amid turning his season around.

Lee is now the No. 6 prospect in the Tigers farm system, according to Signed as an 18-year-old from Taiwan two years ago, Lee's future as an MLB player is still very much unknown. The 20-year-old does seem to have plenty of upside in light of his performance for Single-A Jersey Shore. In 64 games this season, Lee is hitting .283 with a .372 on-base percentage. He has five home runs and 14 stolen bases.

When the Tigers signed Lorenzen in December, Detroit had hoped the pitcher would be part of a team that threatened to make the playoffs. The Tigers' rebuild hasn't gone as planned, and the team is on pace to lose at least 90 games for the fifth straight 162-game season. Detroit had little choice but to be deadline sellers, once again, and it received a fair return for its top trade piece.

Tigers Trade Grade: B-