Leyton Orient 0 Carlisle United 0

The visitors, who started the game at the top, hung on bravely for a point but it allowed Grimsby to take over as the new league leaders.

Orient had two penalty claims turned down by referee Nick Fletcher, but the official also chalked out a Carlisle goal just before the break.

In an enthralling clash it was Carlisle who were quickest out of the blocks and Orient goalkeeper Glyn Garner was forced into four early saves, the best of which saw him tip Adam Murray's 25-yard drive away for a corner.

But Orient clawed their way back into the contest and Craig Easton shot inches wide before the Scot had a penalty claim turned down four minutes later.

Matt Lockwood sent Joe Keith clear and when Keiren Westwood blocked his shot Easton fired in the rebound that struck Murray's hand, but referee Fletcher waved away Orient's frantic claims.

The home side's recent signing Paul Connor, making his first start, was then denied by Westwood, but Carlisle were always dangerous on the break and Garner was forced into another smart stop when Derek Holmes tried his luck from 30 yards.

Holmes then had a goal ruled out on the stroke of half-time for a foul after heading in Chris Lumsdon's corner.

In the second half, Orient took a vice-like grip but despite constant pressure could not break down Carlisle's stubborn defence.

Easton saw a free-kick tipped over by Westwood who then saved Gaby Zakauni's header.

Orient's top scorer Gary Alexander then headed his side's best chance over from close range.