Aston Villa central defender James Collins has been ruled out of Tuesday's home Barclays Premier League clash against Bolton with a groin injury suffered during Saturday's goalless draw with Sunderland.
Right-back Alan Hutton is poised to return to the starting line-up with Carlos Cuellar switching into the centre of the defence to partner Nathan Baker.
Villa will give a late fitness test to striker and current skipper Gabriel Agbonlahor, who suffered a shoulder setback against the Black Cats. If he is ruled out, Emile Heskey is on stand-by to replace him with Cuellar taking over the armband.
Coyle's problems are in midfield, where long-term absentees Stuart Holden, Lee Chung-yong and Fabrice Muamba have been joined on the sidelines by Darren Pratley and Mark Davies.
It means Coyle may turn to Vela for Tuesday's crucial clash against Villa. "It won't faze us because he [Vela] has the ability," said Coyle.
Playmaker Davies became the club's latest injury worry when he picked up a leg injury which forced him to miss training on Monday. Coyle remains optimistic he will be fit to play against Villa, but he will still be without Holden, Chung-yong, Mears and Muamba.
I'm on Shay Given, Eric Lichaj (USA! USA!), Ryo Miyaichi, Barry Bannan (very disappointed with that pick so far), and Andreas Weimann.