Justin Rose withdrew from the Heritage tournament at Hilton Head before his second round today because of back trouble.

But as he departed, fellow Englishmen Nick Dougherty and Brian Davis took over at the top of the leaderboard. Among the early starters on day two, they each added an early birdie to their opening 67s.

Rose, who jointly led The Masters after the first round last week before falling back to 36th place, struggled to a five over par 76 yesterday and decided not to risk further aggravating the problem.

The 27-year-old, last season's European number one and second in the current Ryder Cup standings, was forced into two lay-offs around this time last year because of back pains and took a long winter break to work on his fitness.

He is due back in action at the Wachovia Championship in two weeks' time.

Dougherty and Davis were on five under par after six and five holes, respectively, of their second rounds and shared the lead with former Open champion Justin Leonard, who had yet to tee off again.

Davis Love and Lucas Glover, also round in 66 yesterday, slipped back into the group on four under.