ED Jackson is set to provide Newport Gwent Dragons with a back row fitness boost for Friday's Guinness Pro12 encounter with Ulster in Belfast.

The number eight has made a faster-than-expected return from a hamstring injury and is in contention for a starting spot at Ravenhill.

The 27-year-old Englishman is ready to come straight back into the XV if Nick Crosswell fails to recover from a leg injury suffered in last Friday's excellent 23-13 win against Leinster at Rodney Parade.

Lewis Evans will miss the trip to Ireland with a calf problem but the Dragons do have Ben White as an option at blindside flanker after the 32-year-old Australian signed on a three-week loan from Exeter.

"At the moment it looks like Crosswell (will start) but he hasn't been able to train and is still recovering while thankfully Ed Jackson was able to take part in units training on Tuesday afternoon," said Jones.

"It will be one of those two fellas because there was no reaction for Ed while Crosswell is heading in the right direction and will start if he is ok on Thursday morning."

The Dragons were forced to play lock Rynard Landman as an emergency blindside flanker in the win against Leinster in the absence of Evans, Jackson, Ollie Griffiths (hamstring), James Thomas (back), Andrew Coombs (knee) and Taulupe Faletau (Wales duty).

However, the Rodney Parade region are set to have specialists across the back row in Belfast with Nic Cudd continuing at openside flanker and James Benjamin among the replacements.

The arrival of 6t 4ins White provides them with a heftier option at blindside and centre Adam Hughes, who played alongside the former Cardiff Blues flanker at Exeter, believes he is a good fit.

"He will be great for us and will bring real 'dog' to the team," said Hughes. "He will compete for everything and won't stop working.

"He has a real edge to him, which all teams need so I am looking forward to seeing him play. I know the way Exeter prepare their players and I know he will be ready to step up to the plate straight away."

A late call will be made on captain Rhys Thomas although Elliot Dee is set to get the start at hooker with Rhys Buckley in contention to be his back-up.

Nick Scott is in pole position to start on the wing in the absence of Hallam Amos, who is hoping to get the nod for Wales' Six Nations opener in Dublin.

Ulster have six players in the Ireland squad – hookers Rory Best and Rob Herring, fly-half Paddy Jackson, centres Luke Marshall and Stuart McCloskey and wing Andrew Trimble.

The Dragons have won just once in Belfast – a 16-14 success in 2008/9 – and were downed 19-12 when the sides met at Rodney Parade earlier this season.