Ulster coach Neil Doak may not have to scale the injury mountain that Matt O'Connor has to deal with at Leinster but he must plan without five of his key international players with French giants Toulon hoping to cast a shadow over Ravenhill this weekend.

The big toe of Ireland and Ulster winger, Andrew Trimble, has put the boot into Doaks' best laid plans.

Trimble will be out for some months as Ulster seek opinion how to best manage the injury.

With centre Luke Marshall damaging ligaments in his left knee, he won't be available until December, while Doak also faces the reigning champions of France and Europe without long-term injured South African scrumhalf Ruan Pienaar and Irish locks Iain Henderson and Dan Touhy.

Best season

While Marshall had been ousted from his starting position by Stuart McCloskey, Trimble had just come off the best season of his career. All three Ulstermen also miss out on inclusion in Joe Schmidt’s 37 man squad announced yesterday for the Autumn Series against South Africa, Georgia and Australia.

“Yeah, look you lose them at any time of the season and it’s pretty tough to take, especially the way Andrew’s been playing,” said Doak yesterday.

“Obviously Luke had a few niggles early on in the season and he was given a run with the Ravens where he picked up another bump, so he’s out.

“But hopefully they will get back on the paddock soon. To lose two quality guys like that and obviously the internationals, it puts a bit of a hole in your squad.”

Toulon promises to bring a combination of panache and brawn to Belfast. They have a heady mix of the two as Ulster try and improve on the accuracy of their play that let them down in the first half last week against Leicester in Welford Road.

Like Munster, Ulster chased a 16-point deficit going in at half-time but unlike their Irish counterparts were unable to create the platform that delivered the win and almost a chuckle from coach Anthony Foley.

“Look we struggled a bit with possession in the first half and no tempo in the game and unable to create what we’d been working on all week,” adds Doak.

“But credit to the boys to come back after 16 points down. Maybe if we had a little more confidence we might have been able to stretch them a little bit more and a little bit of luck as well we might have come out of it with a draw.

“We have definitely got to make sure we are more accurate this weekend because Toulon are a quality side across the board with the players they have.

“It will be a tough afternoon if we are not accurate.”

Ball retention

Doak has combed through the match against Leicester and points to Ulster’s unusual generosity with possession. They didn’t respect the ball enough. The English side scored 10 points off the province’s hand overs, one intercept try and one penalty – Leicester won a scrum that ended up being a penalty.

Against a squad of international aristocrats, who killed Leinster hopes in the knockout stage last year, a similar sort of largesse will constitute self harm.

Doak appreciates a second pool defeat would be miserable for the plan of getting out of the group.

But from the second-half performance last week he can believe in the Ulster players and hope Scarlets can put a dent in Leicester.

“Sometimes you don’t get the platform or the things going for you that you’ve been working on all week. We had to dig in and haul ourselves back into that game,” he says.

“Toulon are a quality side. I don’t think there will be any doubt in anyone’s mind about the mental state of the Ulster players.

“It was just a bit of inaccuracy from us as a collective that gave them opportunities.”