Grayson was left scratching his head after Jermaine Beckford failed to score from the spot during Tuesday night's 1-1 draw with Carlisle United, the second time a United player has missed a penalty this season and the sixth unsuccessful attempt in Grayson's 10 months as manager at Elland Road.

Leeds' strike rate from 12 yards stands at one conversion from seven efforts under their present boss and Grayson has worked in vain to find a solution to a bewildering problem.

Beckford, Luciano Becchio, Robert Snodgrass and former loanee Lee Trundle have all been nominated to step forward, but Snodgrass' successful finish at Leyton Orient last season is the only time that a United player has bucked the trend of failure.

The club were reprieved on Tuesday when Beckford's tame strike came back off Carlisle goalkeeper Lenny Pidgeley and presented him with a simple tap-in, but Grayson is more aware than ever of the need to resolve the issue of penalty-taking.

Grayson said: "I'm frustrated that we've missed another one, although obviously Jermaine got the rebound against Carlisle.

"For the previous 10 days, Jermaine was practising half a dozen penalties at least after training and putting every one of them into the top corners.

"He felt confident enough to take it on Tuesday.

"It's an issue that's driving me mad and I just want somebody who's going to score whenever we get a penalty.

"Maybe I could get someone in who can deal with this.

"It's a strange scenario. Jermaine looked fully confident and full credit to him for reacting well to the second phase of it, but he's missed again."

Midfielder Michael Doyle – signed on loan by Leeds from Coventry City in August – admitted that he was also mystified by the failure to find the net from the spot.

Doyle said: "I didn't realise it was a problem until somebody mentioned it to me but there's definitely something strange going on.

"I used to take penalties at Coventry and scored a few but I was kicked off them after I missed one.

"I'd be happy enough to step up and take them if I was asked to, but the way my shooting has been going in the last few weeks, I don't think anyone would be too confident in me."