Rory McIlory is facing an uphill battle to retain his FedEx Cup title following a mixed second round at the BMW Championship in Chicago.

The County Down man needs a strong showing in this tournament at Conway Farms to keep his hopes of retaining the FedEx Cup alive.

But his two under par 69 may not be enough to keep him in contention ahead of the weekend's action. He is on minus one after two rounds, well back on leader Marc Leishman, who produced another fine performance at Conway Farms.

After a steady start, making par on the first five holes, a double bogey on the par-3 sixth and a bogey on the 13th saw McIlroy see out the round at two-under 69.

Australian Leishman, who finished day one as clubhouse leader, held on to the top spot at seven-under 64 at the penultimate play-off event for the season-ending tournament.

After claiming 10 birdies during round one, the 33-year-old shot eight on Friday, again just dropping one shot on the 17th hole of the Chicago course.

It was a different tale on the par 3 hole for fellow Australian Jason Day, who excited the crowd with a hole-in-one. For his efforts, BMW has made a $100,000 donation to the Western Golf Association and Evans Scholars Foundation.

The 29-year-old came back from three bogeys to put in another spectacular performance with an eagle on the 14th, ending round two six-under 65.

Also closing the gap on Leishman is Rickie Fowler, who on day one had a run of six birdies.

Finishing the second round seven-under 64, the American shot three birdies before the turn on Friday, followed by another three on the back nine, impressing the spectators with an eagle on the par-5 15th hole.

Leishman, who goes into the weekend with a three-shot lead over Day and Fowler, told the PGA website: "The game's feeling really good. Obviously rolling the putts really well.

"But you still have to give yourself the opportunity. So, excited about the first two rounds, but a lot of work to do.

"And last week I showed that a couple of shots going in the back nine is not enough. So, hopefully I can keep doing what I'm doing. A lot of great players just behind me."

Round two did not fare much better for Rory McIlroy, whose hopes of earning the chance to retain his FedEx Cup title faded further as he languished one under par in joint 50th place.

Meanwhile, Justin Rose finished the second round in 68 to leave him seven-under overall and joint 12th on the leader board, with fellow Englishman Paul Casey one shot behind in 22nd place.