AUGUSTA, Ga. – Phil Mickelson acknowledged Sunday that time is having an effect on him in major championships.

At 47, he was bidding this week to become the oldest Masters winner, but he barely made the cut. He will turn 48 on Saturday of the next major, the U.S. Open at Shinnecock Hills, where he once again will be trying to complete the career Grand Slam.

“I put a little bit too much pressure on myself in the majors now, because I know that I don't have a ton of time to win them, especially U.S. Opens,” Mickelson said after shooting a 5-under 67 in the final round to finish at 2 over par. “But these next two U.S. Opens, Shinnecock and Pebble Beach, give me two really good opportunities. So, I need to keep my game, get my game sharp. I really need to be on those weeks, and, in the past, I've been on at Shinnecock, and I'm hopeful to do it again.”

Mickelson finished second at the U.S. Open at Shinnecock Hills in ’04, one of his six second-place finishes in the championship.

With Rory McIlroy trying to complete the career Grand Slam at Augusta National on Sunday, with Jordan Spieth looking to complete it at the PGA Championship at Bellerive Country Club in August, Mickelson was asked how much he would like to see all three of them pull it off this year.

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“I think that it would be really cool if any of us, or all, were able to do it,” Mickelson said. “It's one of those career milestones that set you apart from all players, that show you are a complete player.

“They will get it done, but I need to get it done soon.”

Mickelson closed strong Sunday at the Masters with a 5-under-par 67, but he started the day 21 shots off the lead.

“It's never easy to be out here knowing what you're missing out on,” Mickelson said. “With that back nine here, Sunday at the Masters, and not having a chance, it's difficult, because you know what you're missing out on, and you know what special things happen on that back nine, how fun it is to be a part of it, to be in the mix.”