Paul McKee was almost two seconds down on his personal best

McKee clocked 47.49 in a race won by Olympic and world champion Jeremy Wariner in 44.43.

"Maybe there was a bit of tiredness there after two hard weeks of training in Portugal recently," said McKee.

"I also didn't run the best tactical race as I was using Otis Harris outside me as my marker and he ran 46.83, which was way off his personal best."

Harris won the Olympic silver medal behind Wariner in Athens three years ago.

Others to struggle in Saturday's race included Australia's Commonwealth champion John Steffensen whose time of 46.65 was nearly two seconds outside his PB.

McKee will hope for better when he runs in Belgrade on Tuesday.

He added: "I'm fairly hopeful I will be able to run at least a second quicker there because I've done that before in previous seasons after I've run mid-47s in my opener.

"I was very rusty tonight but things will hopefully be better after a couple of days of rest."

African record holder Gary Kikaya of the Congo was second behind Wariner in 44.77 while American Darold Williamson was third in 45.37.

Eva Massey will be in action in Bedford over the weekend

Meanwhile, new Northern Ireland shot putt record holder Eva Massey is among the 14 local hopefuls in action at the UK Inter Counties Championship at Bedford on Sunday and Monday.

Massey's new NI record of 16.60m added 29 centimetres to Mary Peters' mark set in 1976 and she is now hoping to earn selection for Britain's European Cup team next month.

Kelly Reid may have ambitions of improving her 1500m personal best after producing a fine indoor season while Jill Shannon looks capable of challenging Sharon Hatch's low key NI record of just under 16.19.

Current Inter Counties javelin champion Michael Allen is ruled out by injury but Laura Kerr may get close to her own NI record following a useful early season throw of 47.85m when winning the Irish Universities title.

Other local competitors include Stephen Scullion who will be hoping for a European Junior Steeplechase qualifying time of 9 minutes 10 secs.

Paul Hamilton (City of Derry 400m), Michael Dyer (North Down 800m), Paul Pollock (Abbey 1500m), Luke Reynolds (North Down 110m hurdles), Thomas Patton (Loughborough 400m hurdles), Alan Kennedy (Abbey triple jump), Jeremy Harper (North Down discus) and Sarah Quinn (City of Lisburn 400m) will also be in action.