Rangers youngster Ross McCausland called up to senior Northern Ireland squad for fixtures against Finland and Denmark

The 20-year-old, who won a penalty and had his first-half strike chalked off in an impressive display for the Glasgow giants, steps up from the U21 side with QPR winger Paul Smyth set to miss Friday’s trip to Helsinki, but he could be available against Denmark on Monday.

Manchester United defender Jonny Evans had already been ruled out after suffering a thigh strain in Champions League action while goalkeeper Bailey Peacock-Farrell remains a major doubt for the double-header with a knee injury and Paddy Lane (calf) is also struggling.

Lane’s Portsmouth teammate Terry Devlin and West Ham United youngster Michael Forbes have been called upon by Michael O’Neill to boost numbers in training.

In more positive news, Derby County striker Conor Washington was a doubt, but he had a scan at this club on Monday and has been given the all clear to join up with the squad.

Northern Ireland will be looking to end what has been a miserable qualifying campaign on a high and add to their two wins over San Marino.

"It's been a challenging campaign, we have had a lot of players missing, we're well into double figures for this game now, but we'll put a team on the pitch that will be well prepared," O'Neill told BBC Sport NI. "We'll be asking a lot of some younger players but that's the nature of international football.

"Every time we come together it's an opportunity to progress, to get to know the lads a little bit better, getting the younger players to understand how we want to work.

"We don't play again until March so we want a positive camp and obviously good performances and hopefully two positive results.”

Linfield youth product McCausland has progressed through the Northern Ireland underage ranks and O’Neill labelled him as an “exciting young player”.

"We've known Ross right through and we had him with the senior camp in the summer," he added. "I'm pleased he has made the breakthrough because it can be difficult for a young player at a club like Rangers and certainly a change in manager seems to have helped him and he's making the most of it.

"He's an exciting young player - he just has to continue in the vein of form that he's in.

"Once you have that first-team experience you gather belief in yourself as well. He's not a boy who is short in confidence anyhow, so it's good to have him in."