World No.1 Rory McIlroy admitted on Friday he needs to sharpen up with the Masters only weeks away, as he looked set to miss the cut at the rain-hit US PGA Tour’s Honda Classic.

The 25-year-old from Northern Ireland found just one birdie with five bogeys in a four-over-par 74.

That put him at a seven-over for the tournament, three shots over the projected cut line when darkness halted the second round of the $US6.1 million ($A7.83 million) event in Florida.

When play was halted for the day, Brendan Steele was atop the leaderboard at eight-under through four holes, two shots ahead of Patrick Reed, who finished with a 67.

Of the Australians, Robert Allenby (69) sits tied for 33rd at one-over and Marc Leishman (69) is a stroke further back.

“I don’t like missing cuts,” said McIlroy, who last missed a cut on US soil at the 2012 US Open, but missed the cut at the European Tour’s Irish Open last June.

“You want to be playing on the weekend and I’m not there,” added McIlroy, who was already looking forward to next week’s World Golf Championships event at Doral in Miami.

Jim Herman, the surprise first-round leader, didn’t tee off until after 5pm because of two weather delays lasting a total of three hours and 45 minutes. Herman remained at five-under through three holes.

The projected cut line had risen from three-over par to four-over, but McIlroy was resigned to missing it.

“I’ve just got to regroup and put some work in and get ready for Miami next week,” he said.

In two days, McIlroy hit only 14 of 28 greens in regulation.

It was a disappointing performance after McIlroy insisted on Thursday he could still turn things around after a three-over 73 in the wind-swept opening round.