Shane Lowry will play in the final two rounds of the Masters but Graeme McDowell missed the cut by one shot.
The Open champion resumed his second round on the 11th hole, right on the cut mark of even par. He dropped a shot on 12 but hit birdies on 13 and 14 to finish with a 69 that left him one under.
Lowry will begin his third round within the hour as tournament officials at Augusta scramble to make up for weather delays on Thursday that have disrupted the schedule.
Former US Open champion McDowell resumed with a bogey on 9 and looked doomed when he went to +2 on 16 but a birdie on the 17th gave him a chance to make a great escape on the 18th.
However, a second shot to the back of the green left him an uphill putt that was one foot short.
The top three players in the world are part of a five-way tie for the lead.
Spain's Jon Rahm completed a second round of 66 on Saturday to join world number one Dustin Johnson and number three Justin Thomas on nine under par, with Australia's Cameron Smith and Mexico's Abraham Ancer also on the same score.
Rory McIlroy is best of the Irish on -3, leaving him inside the top 30. Amateur James Sugrue (+4) will miss the final two rounds.
"I've known for a while the guys that have been at nine under par," Rahm said. "It's going to be a good weekend.
"I feel like if you're a golf fan you have some of the top players in the world there and many others playing great golf, so this weekend with good weather, faster greens, it should be fun to watch."
Rahm immediately moved into a share of the lead when play in the delayed second round resumed on Saturday morning, the world number two holing from short range for birdie on the 13th.
A good chance to take the outright lead on the 14th went begging and Rahm then looked set to bogey the par-five 15th after opting not to go for the green in two.
The 26-year-old fired his third shot over the green and left his pitch back short of the putting surface, only to promptly chip in for an unlikely par.
Playing alongside Rahm, Bryson DeChambeau had missed his eagle attempt on the 13th when play resumed, but the resulting birdie was his second in succession and was followed by further gains on the 14th and 16th.
However, the US Open champion then bogeyed the last two holes to fall back to level par and faced an anxious wait before just squeezing inside the cut mark, where he was joined by former champions Jordan Spieth and Charl Schwartzel.