Going into the tournament there was a lot of talk centering on how Aronimink could prove too easy for the world’s best.
The last men’s tournament held here, a PGA Tour event in 2018, was won by Keegan Bradley who defeated Justin Rose in a play-off after they finished on 20 under par – although rain helped soften the greens and contribute to low scoring.
And this week, even if bombed drives missed wide fairways, the belief was that players would be able to gouge wedges out of the thick rough onto greens and lead to a putt-off.
The PGA of America has responded by setting up the course in a manner which aimed to disprove that.
The rough has largely been penal for those who have been unable to keep the ball on the fairways, while the severity of the slopes on the greens have generally caused havoc, with more three-putts after two rounds than during the whole of the Masters.
McIlroy suffered on Thursday when his wayward driving was heavily punished, but spending extra time on the range after his opening round to “find feeling” paid off on Friday.
Hitting more fairways set up more birdie chances and eliminated mistakes in one of only two bogey-free rounds.
“I saw that no-one was really getting away so I thought if I could get back to even par for the tournament I’d be right in there,” McIlroy told BBC Sport NI.
“I didn’t quite get there but I still think at one over I’ve got a great chance over the last couple days.”
Missing fairways did not hamper McNealy too much, however.
The 30-year-old former world number one amateur ranks tied 143rd – out of a 156-man field – with his driving accuracy – but has used his short irons superbly to launch a challenge.
“I think this is one of the few courses I can compete on without hitting enough fairways, I think the missed fairways penalty isn’t as bad as other places,” he said.
“Fairways are definitely easier to control the ball and I hope to hit more this weekend.”