Dan McFarland says the decision to leave John Cooney out of the Ulster starting team for the Guinness Pro14 final is the toughest he has had to make as a coach.

The Ireland scrum-half will be on the bench against Leinster on Saturday with former All Black Alby Mathewson (34) at nine in his stead.

Speaking ahead of the domestic decider, Ulster head coach McFarland opened up about the difficulty in coming to his final decision on that position.

"That was definitively the most difficult selection decision that I've ever been involved in - and I've been involved in a lot," he said.

 John Cooney against 

"They are two excellent number nines and Alby's playing the better rugby at the moment.

"I feel really lucky that us as a club have got two nines of that quality and the fact that we're able to look to John coming off the bench as Alby did and influence the game and change the way the game is played potentially in the second half."

One player included in the starting team is captain Iain Henderson, who returns after recovering from a hip injury, and McFarland is glad to have the Ireland second row back for the big occasion.

"It's terrific to have Iain back. He's the captain of the club and we know what Iain can do for us in those big games so it's great to have him back in the fold," he said.

Addressing Leinster's decision to leave Johnny Sexton on the bench for the final, McFarland pointed out that his out-half replacement Ross Byrne is "a really good player and led them to a win over us in the quarter-final last year so he's got a history there."

Follow the Pro14 final between Leinster and Ulster (7.35pm Saturday) with our live blog on RTÉ Sport Online and the RTÉ News app or listen to live commentary on RTÉ Radio 1.