Trimble, now nicknamed Sparky after last week’s incognito second-half performance at Ravenhill where he dressed up as the Ulster mascot, has recovered quicker than expected from finger surgery and fills in for British and Lions star Tommy Bowe, who failed a fitness test on the dead leg he picked up against Treviso.
Trimble is the only change in the three-quarter line which otherwise remains intact after full-back Craig Gilroy recovered from a bruised foot.
There are three changes up front with Nick Williams starting at number eight in place of Roger Wilson, who moves to the bench, while a fit again Declan Fitzpatrick replaces Rickard Lutton at tight-head. The big bonus for Ulster is the return of skipper Johann Muller. He partners Dan Tuohy at lock, with Iain Henderson, who is recovering from a shoulder stinger, in the replacements where he is joined by fit-again Ireland centre Stuart Olding.
A fans’ favourite, Trimble will be making his 163rd appearance for Ulster for whom he has scored 64 tries, 12 of them last season. He is likely to be busy against second-placed Ospreys for whom Alun Wynn Jones will be making his 150th appearance when he leads a side packed with talent and five of his fellow colleagues.
That fact, says Ulster back’s coach Neil Doak, will be the perfect preparation for next week’s Heineken Cup opener against Leicester Tigers.
“There are not very many easy games now in this league now, but this is one that’s maybe a notch up from the average,” explained Doak.
“Even though you’d be worried about picking up some bumps and bruises, it’s good to have a tough game in some ways to get us ready for Europe.
“We know there won’t be too many openings so when we do get a chance we will need to be clinical if we’re to get something from the game.”
ULSTER: C Gilroy; A Trimble, J Payne, L Marshall, M Allen; P Jackson, P Marshall; T Court, R Best, D Fitzpatrick, J Muller, capt, D Tuohy, R Diack, C Henry, N Williams.
Replacements: R Herring, C Black, B Ross, I Henderson, R Wilson, M Heaney, S Olding, D Cave.