Celtic Cup Quarter-Final: Saturday, April 30Neath-Swansea Ospreys v Ulster, St Helen's, 5.30pm (live S4C)
Both Humphreys - who missed Ulster's last two outings - and mnternational winger Tyrone Howe - fit again after a groin strain - are the only changes in Mark McCall's side as they begin their defence of the Celtic Cup away to reigning League champions the Ospreys.
Saturday's opposition boast a very healthy six wins from six at St Helen's in recent times, and the quarter-final clash marks their last outing at the ground before a switch to their new Morfa stadium next season.
If the Welsh region's home form has been excellent, Ulster's road trips have been at the opposite end of the spectrum. Eight straight defeats away from Ravenhill have severely dented Mark McCall's side's chances of League and Heineken Cup progression this season.
Still, the Ospreys had to rely solely on Wales and Lions centre Gavin Henson to pocket a 22-21 over the province at the same venue in January. He scored a converted try and kicked five penalties, including the injury-time winner, to Ulster touch downs from Andy Maxwell and Tommy Bowe and 11 points from Humphreys' right boot.
One-cap Ireland winger Bowe has been one of the shining lights for coach McCall this season, ending the league campaign with a run of three tries in five starts.
McCall's men will want to put on a good show in what could prove to be Andy Ward - the long-time Ulster skipper - lock Gary Longwell and replacement scrum-half Neil Doak's final outings in a white shirt.
Paddy Wallace and Scott Young make way for Humphreys and Howe as McCall's charges hope to build on their final league win - a 16-3 defeat of the Scarlets - a fortnight ago.
Scrum-half Kieran Campbell also starts after doubts surrounding a rib injury the 25-year-old picked up against the Scarlets were dispersed.
McCall - although boasting a near full-strength side - admits he is under no illusions as to what shape Ulster have to be in to compete with Lyn Jones' men.
"The Ospreys won the Celtic League at a canter, have a host of Welsh internationals and are a side we have a lot of respect for.
"At the same time, sporadically this season we have shown at our very best we can compete with anybody and that must be the case on Saturday.
"If we are not at our best, we will lose," said the former Ireland Under-21 coach.
The Ulster branch meanwhile, have confirmed an August pre-season friendly against the Rotherham Titans.
English National Division One side Rotherham - who signed their new Chief Executive Andre Bester from AIB League semi-finalists Belfast Harlequins earlier this season - will line out against Ulster at Ravenhill on Friday, August 26 (kick-off 7.30pm).
Head-to-head since 2003: Ospreys 3, Ulster 1Celtic form: Ospreys: WWWWW; Ulster: WLWLWTop League scorers: Ospreys: Gavin Henson 175 points / Jason Spice 8 tries; Ulster: David Humphreys 81 / Tommy Bowe 8Cup records: 03/04: Ospreys: First round (lost 21-35 v Leinster (away)); Ulster: Winners (won 27-21 v Edinburgh (Murrayfield))
Backs: Stefan Terblanche, Richard Mustoe, Shane Williams, Andrew Bishop, David Bishop, Elvis Seveali'i, Gavin Henson, Matthew Jones, Shaun Connor, Jason Spice.
Forwards: Paul James, Duncan Jones, Andrew Millward, Barry Williams (Capt), Richard Hibbard, Lyndon Bateman, Brent Cockbain, Jonathan Thomas, James Bater, Ryan Jones, Richard Pugh, Steve Tandy, Adam Jones.
(16) Rory Best(17) Ronan McCormack(18) Rowan Frost(19) Campbell Feather(20) Neil Doak(21) Paddy Wallace(22) Andrew Maxwell
Referee: Andrew Ireland (Scotland)