Ireland wing Robert Baloucoune and Scotland prop Rory Sutherland have been ruled out of Ulster's United Rugby Championship game against Zebre at Kingspan Stadium through injury.

Sutherland sustained a knee injury in Scotland's defeat to the All Blacks.

The URC returns after a four-week break for the autumn international series.

Ulster have not placed a timeline on either player's return, but neither injury is expected to be long-term.

Jacob Stockdale and Ethan McIlroy are possible starters on the wing against the Italians, while Andy Warwick and Eric O'Sullivan will compete for the loosehead prop berth in the absence of British and Irish Lion Sutherland.

Winger Aaron Sexton is also sidelined after undergoing surgery on a thumb ligament injury picked up while playing for Malone in the All-Ireland League.

The trio join Will Addison, Ian Madigan, Jude Postlethwaite and Sean Reffell on the list of players unavailable for the game as Ulster return to action for the first time since their win over Munster on 29 October.

"We have been training for a few weeks with no game to look forward to so the guys are really lapping up the detail of the start of a match week," said Ulster assistant coach Dan Soper.

"Looking at an opposition brings an excitement so while everyone enjoyed the break and it was nice to get it, we are really looking forward to getting back into action."

Ulster sit second in the table with five wins from their first six games, while Zebre are bottom after losing each of their first seven fixtures.