Phil Mickelson’s hopes of completing a career Grand Slam have once again become a talking point as he prepares for the 2025 U.S. Open at Oakmont. While the 54-year-old is currently making his seventh start of the season on LIV Golf, fans are already debating whether he can finally capture the only Major that has eluded him.Mickelson is putting on a solid show at the Robert Trent Jones Golf Club, currently tied for fifth after the first round. He recorded birdies on the 6th, 7th, 10th, 12th, 13th, and 14th holes, with bogeys on the 8th, 11th, and 16th. His strong play has sparked hope among some but skepticism among many others.NUCLR Golf shared a clip of Mickelson’s current round, asking:“Will Phil complete the career Grand Slam?”Several fans in the comments doubted his chances. One user wrote:“He won’t make the cut at Oakmont…that’s my guess.”Another added:“I love Phil. But he will end the tournament +8.”“Absolutely no chance, not even with a 10 shot start ⛳️,” a fan wrote.A fourth comment read:“Not a chance.”One user also pointed out his past near-misses, saying:“How many times has he finished 2nd in the US Open? He pissed away that championship a long time ago!”Despite coming close several times, Mickelson has never won the U.S. Open, finishing runner-up a record six times in 1999, 2002, 2004, 2006, 2009, and 2013.Currently ranked 1162nd on the Official World Golf Ranking, Phil Mickelson has missed the cut at both the 2025 Masters and PGA Championship. His best finish this season came at LIV Golf Hong Kong, where he placed solo third at 14-under.U.S. Open 2025 could be Phil Mickelson’s last appearance at the majorPhil Mickelson recently admitted that the 2025 U.S. Open at Oakmont could be his final appearance at the tournament. Speaking at a press conference ahead of LIV Golf Virginia, Lefty said:"There's a high likelihood that it will be [my last U.S. Open], but I haven't really thought about it too much"Mickelson’s five-year exemption into the U.S. Open, earned through his 2021 PGA Championship win, expires this year. With no wins or high finishes in recent majors, and ranked 15th in the LIV Golf standings, his only way back might be through qualifying or by leading the LIV Golf standings at the end of the season.As he approaches his 55th birthday, Mickelson remains focused on contributing positively to his LIV Golf team, the HyFlyers. He emphasized his commitment to the team's success, stating he would step aside if he no longer contributed positively.The 2025 U.S. Open, which begins June 12 at Oakmont Country Club, could be Phil Mickelson’s final shot at completing the career Grand Slam.