McIlroy joined 18-time major champion Nicklaus as part of an elite group of six players who have completed a career grand slam of all four major tournaments by winning The Masters at Augusta in April.
The world number two subsequently tied for 47th place at the US PGA Championship at Quail Hollow and is set to return to competitive action at the Canadian Open on 5 June as he prepares for the season’s third major, the US Open at Oakmont in Pennsylvania, from 12-15 June.
The PGA Tour’s final signature event of the season, the Travelers Championship, will be staged in Connecticut the following week.
“I know he likes to play so many in a row. He likes to play the week before a US Open. And so that’s what he’s doing. So, you know, I really don’t have a comment on it,” added Nicklaus.
“It’s very difficult, very difficult. I mean, I’m a big Rory fan, I always have been. I’m sure that I will remain that way. I just, I was a little surprised, yes.”
