ON-LOAN Plymouth Argyle striker Cillian Sheridan has been given a big challenge by Paul Sturrock. The Pilgrims' manager wants the Irishman to prove that he is worth a place in the Coca-Cola Championship club's starting line-up.

The Republic of Ireland Under-21 international arrived at Home Park with a reputation as a highly promising player when he was borrowed from Celtic in August, but he been unable to fulfil his potential on a consistent basis while performing for Argyle, and it remains to be seen if his loan deal will be extended when it expires at the end of next month.

Sheridan has made only five starting appearances for the Pilgrims, and he has not yet managed to score a goal. He has demonstrated that he does have plenty of talent, notably on his debut as a half-time substitute at home to Queen's Park Rangers in August and away at Newcastle United the following month, but he has failed to convince Sturrock that he is worthy of being a first-team regular.

The Argyle boss has urged the 20-year- old to demonstrate his appetite to play for the Pilgrims. Sturrock said: "I think the boy Sheridan has to appreciate that he has to sway my judgement on selection. The only way he can do that is by training at the moment, or in the bit-parts he has played in games, because there are no reserve games at present.

"If the Sheridan that we saw against Newcastle turned up every week, he would not be out of the team, but the problem is that there is an inconsistency in him due to his naivety and his age," the Scotsman added. "He does have natural talent, but I just feel sometimes that he does not appreciate that being selected is a daily process. That's something I'll just have to remind him about."

Argyle will have a vacancy in their attack today, when they entertain Barnsley at Home Park. Top scorer Jamie Mackie has to serve a one-match ban, and Sheridan is hoping to be asked to plug the gap.

"I need to try to go out and impress again, and kind of start over," Sheridan (pictured left) admitted. "I don't want to go out on loan and then not play, so it's up to me to try to get back into the team. Any half-chance I get, I'll have to take it."

The Irishman's best performance so far came in Argyle's 3-1 defeat at Newcastle two months ago. "For me, it was a good game, but we lost so there was not much to cheer about there," he added.

"I know there's no point in having a game like that and then not doing well in the rest of the games. I know I have to be consistent, and I just have to focus on trying to get back playing again."