DUBLIN, Ohio — Rory McIlroy isn’t playing the Memorial to make sure a rib injury is fully healed before the U.S. Open. Justin Rose cited a sore back in pulling out of the tournament where he earned his first PGA Tour victory. Paul Casey was another withdrawal because of a foot injury that has plagued him before.

Jack Nicklaus said McIlroy texted him to explain what was going on.

But a question about McIlroy led Nicklaus to lament how easy it is for players to withdraw from tournaments, especially as he considered his era with Arnold Palmer and Gary Player.

He said he shared his concerns with PGA Tour Commissioner Jay Monahan.

“You think I had any injuries when I played? Do you think Arnold had any injuries when he played? Do you think Gary had any injuries when he played? How many tournaments do you think that we entered that we withdrew from during the course of our career?” Nicklaus said.

He put his forefinger to his thumb to signal zero.

“Never entered if I wasn’t going to play,” Nicklaus said.

He attributed some of it to money and said he understood withdrawals because “it’s pretty much the norm today.”

“Would they withdraw back 30 years ago? Probably not, because that wasn’t the norm,” Nicklaus said. “We played through it. We had a ton of injuries and I played through it. But that’s sort of the norm today. And the guys … I made my own decisions. I didn’t have an entourage. I didn’t have a fitness trainer. I didn’t have a nutritionist, whatever you all have, somebody to cut my toenails in the morning. I didn’t have any of that. I did that myself.

“I think that entourage helps make that decision for the player, telling them, ‘We think physically this is probably not right for you to play.’ And that’s what their job is,” Nicklaus said.

He said it was annoying for spectators and tournament officials when someone withdraws. As for McIlroy, Nicklaus said the four-time major champion explained his rib injury and Nicklaus said he could sympathize with that.

“The U.S. Open is a big thing in his career,” he said. “And I sort of thought the Memorial Tournament was, too. And he supported us. He’ll come to play every year he can.”