Lemon tonic puts McIlroy in tie for lead with Donald Armed with the love of a good tennis player and the juice of five lemons, Rory McIlroy overcame the effects of sunstroke to claim a share of the halfway lead in Dubai. With one player, Shane Lowry, still connected to a hospital drip after withdrawing from the DP World Tour Championship, McIlroy took his sickness seriously enough to retire early on Thursday with a restorative potion mixed by partner Caroline Wozniacki. A second-round 67 was evidence of Ms Wozniacki's nursing credentials and McIlroy's powers of recovery. Scot Marc Warren also shot a 67 to deny McIlroy his wish to contest the final group today with Luke Donald. Golf's first-in last-out rule means Donald, the third player on 11 under par, will spend the afternoon in the company of Branden Grace. I didn't feel great last night. I guess it's just the Irish skin not used to this sort of sun," McIlroy said. Caroline made me a glass of lemon juice and then I had some sort of vitamin and mineral drink, which made me feel a little better. I think I could have been a couple of shots better out there but tied for the lead going into the last 36 holes is a great position. On a second day of prolific plunder, Donald was heading for a mere 69 until a birdie on the last brought him level with the leaders. It was classic Donald, who has yet to drop a shot this week and whose skinning of the 18th cat proved a lesson for McIlroy. A monster drive encouraged McIlroy to take on the green with his second. A slightly uphill lie, coupled with the creek snaking across the front of the green, forced him wide with the approach and into the long grass at the side of the green. From there he had to settle for par for the second day running. Donald was never going to take it on, choosing instead to lay up 130 yards out, from where he pitched to four feet. Job done. "When you are playing well and really trusting the swing, like I am at the moment, I don't think there is much doubt," Donald said. I had 130 to the flag and it was a perfect number. When you have a perfect number from that kind of distance and you can just hit a full shot, you are pretty sure about getting it close. Of course you are, Luke. The round of the day belonged to Sergio Garcia, who equalled the course record with a 64 despite carding a triple-bogey seven in a run that saw five shots lost to par in as many holes on the back nine. Garcia was one of only eight players to start the day over par. By the close of his round he was briefly the leader in the clubhouse. "I started really well, played nicely on the front nine and birdied 10 and 11," he said. The rollercoaster started on 12. I missed a couple of short ones, followed that with eagle and birdie then hit the worst shot of the round at 16. I just tried to stay calm and figured another birdie coming in would still be a good round. In the end I hit two great shots on 17 and 18 to finish birdie, eagle. In my whole career I don't remember a round like it. Only seven players remain over par. Though Lee Westwood goes into the weekend on three under, his two-over 74 yesterday drew smoke from his ears on the last. After a bogey at 16, Westwood followed up with a double at the next. When his birdie putt lipped out at the last, what little comfort might have been his drained from the day. Westwood's playing partner Louis Oosthuizen closed one off the lead alongside fellow South African Grace. One further back is Joburg's finest, Charl Schwartzel. No matter how they go here, all three will be in front of a clubhouse television today cheering on their oval-ball brothers against the English.