Friday July 15, 2011, 06:55 AM

The second round of the British Open has got under way with English amateur Tom Lewis and Danish veteran Thomas Bjorn hoping to build on their overnight leads.

Lewis, 20, enjoyed a fairytale Open debut at Royal St George's on Thursday, shooting the lowest score by an amateur in Open history to claim a share of the lead alongside Bjorn on five-under-par.

A delighted Lewis remained realistic about his chances of remaining in the hunt however, stressing that with 54 holes still to play on the demanding 7,211-yard links layout anything could happen.

"It's just one day. I'm sure I'm not going to shoot four 65s. I'm going to have tough moments but as long as I limit my mistakes I'll be happy," said Lewis, who had partnered Open legend Tom Watson on Thursday -- the man he was named after by his golf professional father.

Meanwhile Bjorn, who only earned a late place in the field following the injury withdrawal of Vijay Singh, provided Thursday's most heartwarming storyline as he returned to the scene of his infamous 2003 collapse to take the lead.

Bjorn's last appearance at St George's eight years ago saw him blow a three shot lead with four to play to allow unknown American Ben Curtis to swoop in an steal the famous Auld Claret Jug.

Bjorn, whose father died in May, was later overcome with emotion in a press conference when asked about his bereavement.

"I'm sure he would have been very proud," he said, choking back tears.

Whether Lewis and Bjorn will be able to hold off the chasing pack remains to be seen but with brilliant sunshine and very little wind on the course, Friday's second round conditions were perfectly set up for a day of low scoring.

Lewis's second round was due to tee off at 9:31 local time (0831 GMT), while Bjorn had a later start at 12:26 (1126 GMT).

Three players -- 47-year-old Miguel Angel Jimenez of Spain and American duo Lucas Glover and Webb Simpson are just one shot off the pace.

A group 12 players including US PGA champion Martin Kaymer and 2010 US Open winner Graeme McDowell are three off the lead.

Tournament favourite Rory McIlroy, the newly-crowned US Open champion, is six adrift of the leaders after an opening one-over-par 71 but knows better than anyone how quickly a Major championship leaderboard can change.

McIlroy is joined on one-over by the top two ranking players in the world, English pair Luke Donald and Lee Westwood, while top American hope Phil Mickelson, at 41, was just ahead of them at level par.

© 2011 AFP/sid