Phil Mickelson couldn’t pick up Thursday where he left off at the PGA Championship – and that seemed perfectly OK with him.

“I didn’t play well. I shot 3 over,” Mickelson told reporters after an opening 73 at the Charles Schwab Challenge. “But I won the PGA, so ...”

Say no more.

Mickelson was just four days removed from his record-breaking victory at Kiawah Island, where the 50-year-old became the oldest major champion in history. Rather than take the week off to reflect on his historic week at the PGA, he kept his commitment to tee it up at Colonial, where he won in 2000 and ’08.

So calm and in control in the winds in South Carolina, Mickelson described himself as “antsy” and “unsettled” during the opening round. He said he was “trying a little too hard” and couldn’t find the relaxed state of mind that led to his successful week at Kiawah. Now his 3-over start will leave him with work to do to make the weekend in what will be his only start before the U.S. Open.

“You can’t play this course of the rough because then you have tree trouble, which I had repeatedly, and I didn’t putt well,” said Mickelson, who hit just five fairways and nine greens. “But I won the PGA, so I’ll see if I can get it turned around for tomorrow and get a little better focus, a little better energy. ...

“I’ll have some time tonight and tomorrow to get settled in, and hopefully I’ll come back and play a good round. I know even though I didn’t play well today, my game is not far off. I’ve been playing well.”

Mickelson will tee off at 2:06 p.m. ET Friday alongside Jordan Spieth, who opened with 63, and Daniel Berger.