AN IMPROVED performance last weekend may have been enough to end Motherwell's four-game run of defeats by earning them a 2-1 away win against Ross County but Stuart McCall knows his team must move up another gear when they travel to Celtic Park tomorrow.

The Fir Park manager said of Ronny Deila's side: "I certainly think they have improved and got stronger. I watched the European game and Salzburg are a good side.

"Craig Gordon was outstanding and he needed to be but you look at the squad and Leigh Griffiths wasn't even on the bench. Anthony Stokes came on and John Guidetti can come in. It shows you how strong they are.

"They have players fighting for places. [Aleksandar] Tonev was a new face last week and then [Mubarak] Wakaso comes in from nowhere and scores a goal.

"The manager keeps talking about them getting fitter and stronger so that they can press and they certainly seem to be doing that. I watched them against Aberdeen last week and as well as Aberdeen did in certain parts of the game, Celtic could have scored more than twice.

"We need to up our levels of performance anyway. Even though we were delighted with the win last week, it still doesn't mask the fact we were nowhere near as good as we can be. So we need to improve."

Keith Lasley, McCall's captain, added: "I don't think there's any doubt injuries have hampered us in key areas of the park - they would have probably hampered most teams in the league - but beyond that we have been poorer than we know we are capable of.

"But what we did last season, even when we weren't playing so well, was find a way to win games. We've not really managed to do that this year yet but hopefully it will come.

"We still feel that,once we have everyone fit we have a squad that is hopefully capable of challenging in the right areas of the league. It's up to us to try and kick on now and show that."