Tyler Mahle Posts 1.48 ERA as Braves Lead MLB Trade Deadline Impact Ratings

One month after the 2026 MLB trade deadline, Tyler Mahle leads all acquisitions with 1.4 bWAR and a 1.48 ERA through five starts for Atlanta.

Atlanta Braves starter Tyler Mahle has emerged as the most impactful acquisition of the 2026 MLB trade deadline, recording a 1.48 ERA and 1.4 bWAR over his first five starts since moving from San Francisco. Before the trade, Mahle held a 3-9 record with a 5.13 ERA for the Giants, surrendering five runs in his final start for that club—a total equal to the runs he allowed across his first five outings in Atlanta. This performance anchors the Braves' 108.6 post-deadline rating, the highest in the league, despite the Philadelphia Phillies mounting a division challenge with a 19-7 record over the last month. The Phillies improved their win projection by more than five games, the largest uptick among contenders, even as Luis Arraez produced a modest .704 OPS following his arrival.

National League Contenders and Pitching Shifts

The Chicago Cubs rank second in player impact at 6.2, driven by reliever Clay Holmes and starter Kevin Gausman, who has delivered three quality outings out of five. Tyrone Taylor has provided an unexpected offensive boost for Chicago, slashing a 1.027 OPS through 19 games, while Aaron Civale maintains a 1.54 ERA in a multi-inning relief capacity. In Los Angeles, the Dodgers remain at a 100% playoff probability despite a "so-so" team stretch. Their primary acquisition, Tarik Skubal, owns a 3.00 ERA and a 2.28 FIP over five starts but has earned only one win due to limited run support.

San Diego Padres General Manager A.J. Preller increased his team's playoff odds by 29.6% through aggressive moves for Robbie Ray and Casey Mize. While Ray has struggled with walks, Mize has posted an ERA exceeding 6.00 with the Padres. Conversely, the Arizona Diamondbacks saw their postseason chances plummet by 30.2% after making only one move to acquire Lars Nootbaar from St. Louis. The Milwaukee Brewers continue to lead the National League race for the top seed despite Dustin May falling off after two starts and Antonio Senzatela failing to secure a high-leverage role.

American League Wild Card and Division Races

The Toronto Blue Jays sit at a 108.4 rating after replacing Kevin Gausman with Jose Soriano and adding prospect Brett Bateman, who has contributed speed and defense to a team that saw its playoff odds rise by 8.6%. The Tampa Bay Rays have seen their win projection climb to 96.1 games, aided by Liam Hicks’ offensive production and Tyler Wells’ bullpen presence. While Freddy Peralta has managed only two quality starts in five appearances for Tampa, his most recent outing featured six shutout innings against Detroit.

In the AL Central, the Chicago White Sox have maintained better than .500 ball to increase their playoff odds by 20.1%. This surge occurred despite Luis Castillo performing worse than his previous tenure in Seattle and Huascar Brazoban posting a 6.30 ERA and 6.49 FIP before his injury. The New York Yankees have seen a 1.6% increase in postseason probability, though Heliot Ramos hit just .148 in his first month. Luis Garcia Jr. has mitigated that slump with a 133 OPS+ and 0.6 bWAR for the Bronx club.

Impact of Subtraction and Late-Month Moves

The Baltimore Orioles increased their playoff chances by 10.6% despite being in "subtract mode" at the deadline, eventually claiming Luis Robert Jr. off waivers to join Pete Alonso. The Cleveland Guardians received a boost from Jo Adell, though Foster Griffin and Craig Yoho—who holds an ERA over 7.00—have seen mixed results. Texas Rangers’ pickups Adam Macko, Chase Silseth, and Logan O'Hoppe have provided little immediate value, yet the team’s playoff odds rose 13.5% due to divisional trends.

Boston Red Sox lefty Erik Miller has been a standout in the bullpen, but the team has struggled with run prevention, ranking among the bottom five clubs since the deadline. Adley Rutschman has yet to find his rhythm at the plate for Boston, and Curtis Mead suffered an injury in his debut. Outside of the playoff hunt, the Kansas City Royals and New York Mets have improved their play post-deadline. Kansas City has utilized a revamped bullpen featuring Nate Pearson and Craig Kimbrel, while the Mets secured the largest haul of prospects during the July transaction period.