Both men opened with 70 on Thursday.
Matsuyama was having a bogey-free round and started his attack with an eight-foot birdie putt at the par-4 fifth. He bogeyed No. 11 after the suspension, but he re-ignited his round by sinking a monster birdie putt at No. 13 and added another birdie at the 14th.
He was exhausted on the back nine? "That's my plan. Other than that, I'm playing for par".
The Kiwi golfer climbed from 80th to 11th with his 5-under par 66. He had three birdies and one bogey on his card. Not really controlling my thought process, where I want the ball to go. So, the first holes were shaky by any standard and I was three-over.
"Yesterday I struggled with that but I sort of found something in my last couple of tee shots and took that into today and drove it a lot better and gave myself some pretty good looks and took advantage of it".
Dane Thorbjorn Olesen, the joint first round leader with Kisner at four-under, was in the afternoon half of the draw.
Louis Oosthuizen posted a 4-under 67 Friday to join Molinari at 5 under, and Chris Stroud is now 5 under with five holes left to play in his second round. He's been unbelievable at majors in the past few years, and if somebody is going to make a charge from deep, I'm guessing it will be him.
Lahiri said, "Frankly I played solid but it was only in the second nine that I got going". "Hitting fairways are key". A short miss on eighth for birdie was followed by a closing birdie on ninth and that left a good taste and in a good mood for the second day. His only bogey on Friday was on No. 1, a long dogleg par 4.
Matsuyama chips from greenside rough at the par-five 15 to two feet and sinks the putt after play resumed following a one hour 43 minute delay for his fourth birdie in a row. He closed with back-to-back pars. In nine major starts, Koepka has an incredible nine top 25's including three top five's and a win. "It's fantastic how they have been able to make this course so much tougher".
Making an exacting test look nearly easy, he posted an eight-under 134 halfway total, while compatriot Rickie Fowler was the best of the other early starters, five behind after a 70. South Korean An Byeong-Hun also eagled the par-5 seventh in a round of 69 to finish on 140.
USA's Jordan Spieth, aiming to become the youngest player to complete the career Grand Slam, was one over with two holes of the second round to play and two over for the tournament.