Gregor Townsend has not ruled out the possibility of a return to the transfer market to keep Glasgow Warriors' RaboDirect PRO12 play-off ambitions on track.

Speaking ahead of tonight's 1872 Cup encounter with Edinburgh at Scotstoun, in which a win would move the Warriors back into second place in the PRO12 table, Townsend pointed out that a spate of injuries in key positions had stretched the squad's strength in depth close to breaking point.

The problem areas for the Warriors have been at lock and in the midfield. In the former, Tim Swinson is now back in action, but they are still missing Al Kellock and Jonny Gray. The centres who are out of action at the moment are Mark Bennett, Peter Horne and Gabriel Ascarate.

"You never know how you are going to be affected," said Townsend, who pointed out that Glasgow also had a crisis at hooker last season. "It is about making sure you have enough cover and enough quality players. I believe we have that depth of quality, but we are always on the lookout for players who will enhance our squad whether from Scotland or abroad."

Glasgow were transformed by the arrival of Niko Matawalu, Josh Strauss and Sean Maitand last season, but their recruitment was more modest for this campaign. By contrast, Edinburgh have been far more vigorous, and the capital side were given a boost yesterday when Ally Dickinson extended his contract with them for another two years.

It is understood that Glasgow prop Moray Low has been targeted by Aviva Premiership side Exeter Chiefs, but Townsend refused to comment on the issue. However, he did suggest that former Scotland No.8 Richie Vernon's transformation into a centre is almost complete and that he is likely to appear for the club in that role within a few weeks.