​All-Star week in Philadelphia has come and gone, which means it’s time to prepare for the unofficial second half of the season. The Phillies had a good first half considering they experienced a ten-game losing streak and fired their manager in April. They come into their second half opening series with the New York Mets two games behind the Atlanta Braves in the National League East with a record of 54-43. They currently occupy the second NL Wild Card spot and have a three-game lead for a spot in the postseason field. There is work to be done, but the Phillies have placed themselves right in the thick of the NL postseason picture.That doesn’t mean there aren’t glaring weaknesses in this Phillies team though. The upcoming trade deadline will be the biggest chance to improve the roster, but thanks to the Phillies limited trade capital, they will also have to look inward for improvements. There’s no shortage of underperformers on the roster, but these are three that could make a real impact if they find a way to improve.AdvertisementAdvertisementAdvertisementTurner was one of the Phillies best players in 2025 when he won the batting title and dramatically improved his defense resulting in a 5.4 WAR season. He has regressed heavily in each aspect, as he’s hitting .236 and has the fifth most errors (12) of any shortstop in baseball which has resulted in a negative WAR total. His strikeout rate has spiked, up to 22.2% from 16.7% last season. His chase rate is back up in conjunction with that, up over 35% after cutting it down to 31.2% last season.Defensively, Turner has lost all of the gains he made last season. He already has more errors than he had all of last season (8) and is on pace to come close to his brutal 2023 season when he led the majors with 23 errors. It’s even worse if you go by defensive metrics, as his -9 defensive runs saved are tied for second worst in baseball and his -6 defensive run value is fourth worst.AdvertisementAdvertisementAdvertisementThe good news is that Turner has begun to show a pulse offensively for the better part of the last month. Since June 15th, Turner is hitting .286 with a .759 OPS across 106 plate appearances. He started off July well but is currently 1 for his last 13 entering the break. The Phillies need Turner to rediscover some of what made him a batting champion in 2025, because it’s beginning to look like his strong defensive season last year may be an aberration.Alvarado looked to be having a renaissance in 2025 before a PED suspension and injuries completely derailed his season. The Phillies elected to pick up his club option for 2026 anyway, believing that he would rebound after a full offseason reset. That decision is not looking wise, as Alvarado is in the midst of the worst season of his career with a 6.82 ERA through 39 games. Opponents are currently slashing .307/.394/.464 against Alvarado. Yordan Alvarez and Yandy Díaz are the only qualified hitters with at least that slash line o