DENVER, CO - MAY 20: Manager Rob Thomson #59 of the Philadelphia Phillies looks on from the dugout in the first inning against the Colorado Rockies at Coors Field on May 20, 2025 in Denver, Colorado. (Photo by Justin Edmonds/Getty Images)Getty ImagesThe Philadelphia Phillies lost their fifth straight game on Sunday, suffering a sweep at home by the division rival Atlanta Braves and suddenly increasing the pressure on manager Rob Thomson.Thomson was given an extension by the team before the season started but the team has looked to be so far from expectations through the first one-eighth of the season that the possibility of a change at the helm has been raised.Like the (New York) Mets, they are talented enough to snap out of it, The Athletics Ken Rosenthal wrote. If they dont, they could replace Thomson with their first-year bench coach, Don Mattingly, who previously managed the Dodgers and Miami Marlins.MORE FROM FORBESLong-Time Mets Farm Slugger Joins AL Contender After CutBy Peter ChawagaPhiladelphia Phillies Rob Thomson Delivers Frustrated Message After Atlanta Braves SweepThomson offered a more defensive tone than he has so far this season when he addressed the teams struggles after Sundays loss.Everybodys frustrated, Thomson told reporters, according to a postgame video shared by On Pattison. Im telling you nobody is complacent, everybodys working their tails off. Nobodys happy. According to Rosenthal, at least, the only thing that can guarantee Thomsons future for the rest of the season is an improvement in the standings. Without one, the team does seem to have a clear replacement candidate already in the dugout.MORE FROM FORBESBlue Jays Fans Turn On Vladimir Guerrero Jr As Concerns MountBy Peter ChawagaPhiladelphia Phillies Could Turn To New York Yankees Legend Don Mattingly To Replace ManagerPhillies bench coach Don Mattingly served as the Toronto Blue Jays bench coach during their World Series run last year and appeared to have a positive impact on the teams standout batting order. But shortly after the Blue Jays lost to the Los Angeles Dodgers in extra innings of Game 7, Mattingly stepped down and then after a brief interval joined the Phillies as the bench coach. Mattingly coached alongside Thomson for the New York Yankees and his son Preston works in the Phillies front office. But even though that family connection helped bring the six-time New York Yankees All-Star first baseman to Philadelphia, Rosenthal noted that it might be an obstacle in Mattingly replacing Thomson.Its not known whether Mattingly would want the job, Rosenthal added. His son Preston is the Phillies GM, creating a potentially awkward situation. Thomsons staff includes other possible replacements, starting with third-base coach Dusty Wathan.If and when the Phillies determine that they could lose the chance to compete for a World Series with Thomson, it looks like Mattingly would be the teams first choice as a replacement. But Mattingly might prefer to stay out of direct conversations about the teams personnel with his son.Either way, Thomson might have to do more than change his tone if the Phillies cant snap their losing streak.This article was originally published on Forbes.com