LUKE DONALD has a battle on his hands to retain his world number one spot as he trails Colt Knost by 11 shots at the RBC Heritage tournament in South Carolina.
Donald must finish in the top eight or surrender the top spot to Rory McIlroy and is on two over par after a 69 yesterday which was just one shot inside the cut.
Knost leads the way on nine under after a solid 66 and he is two shots ahead of Swede Carl Pettersson who is one clear of Americans Boo Weekly and Harris English.
Ireland's Padraig Harrington couldn't capitalise on his impressive showing at the Masters last week and missed the cut after a 72 left him on four over for the tournament.
Meanwhile, US Masters runner-up Louis Oosthuizen had his second round charge at the Malaysian Open lead halted yesterday when thunderstorms and heavy rain ended play early at the European and Asian Tour event.
Oosthuizen was two-under-par after 12 holes of his round at the Kuala Lumpur Golf and Country Club for a eight-under total.
The South African trails compatriots Hennie Otto and Jbe Kruger by one shot after they fired an eight-under-par 64 and seven-under 65 respectively before the weather turned. Oosthuizen is looking for a fifth win on the European Tour, a triumph that would go a long way to help him overcome the heartbreak of missing out in a playoff at Augusta to American Bubba Watson on Sunday.
After a 30-hour journey to take part in the $2.5m tournament in the Malaysian capital, he followed up his opening round 66 with 10 pars and two birdies on the narrow layout.
The 2010 British Open champion will be one of 75 players who will return early on Saturday to complete their second round.
Asian Tour Order of Merit leader Kruger credited his putting after following up his opening round 70 with a 65 for a share of the lead in the South African-heavy leaderboard. "I think all of us (South Africans) are coming into this tournament with a little bit of form coming back," Kruger said.
"My game is a little bit better. I've been working on a lot of things and it seems to be coming together which is always a good sign."