Head coach Richie Wellens is hoping Leyton Orient have used up their 'bad luck' in a 1-0 FA Cup defeat at Crewe Alexandra.

Bassala Sambou's injury-time goal sent the Railwaymen through to the second round, after O's had seen two goals ruled out and Craig Clay shown a straight red card late on.

And Wellens struggled to hide his frustration as he discussed his League Two-leading side's exit from the competition at Gresty Road.

"There's no point talking about the referee. He was poor in a lot of aspects of the game, probably cost us two goals and then the sending-off," he told the club website.

"We know what Craig is, he's an honest player, he slid in, took the ball and when you take the ball your knee follows through and he caught the lad.

"For me it wasn't even a yellow, never mind a red. We spoke about whether we'll appeal it or not but it was a wrong call.

"We've had a bit of bad luck and hopefully we've used it all up in the cup."

Charlie Kelman had an early effort chalked off, having been adjudged to have fouled Arthur Okonkwo, and substitute Paul Smyth was denied by an offside flag in the final quarter of the match.

And there was even some doubt as to whether the ball had gone out of play in the build-up to Crewe's last-gasp winner.

"Because of the camera angle it's so far away, we need those cameras that zoom in. That was more difficult to tell. I wouldn't begrudge them that goal," added Wellens. 

"The others, their goalkeeper slides out to catch it, it's slipped out, he's dropped it. Kelman comes in and takes one touch, took it round him and then he scores.

"Paul Smyth is onside when he is through one-v-one, but we also have to take our chances.

"We were unlucky with Moncs [George Moncur] which hit the bar, then Smudger has gone through one-on-one and should just square it to Idris [El Mizouni] and it's a guaranteed goal.

"I've been involved in so many games like this where if you don't take your chances you run the risk of losing 1-0."

O's were once again cheered on by their loyal travelling supporters in a crowd of 2,104 with the club having laid on free coach travel.

And Wellens admitted he was disappointed for them, having seen his side suffer just one defeat in 16 league matches to date this season.

"I'm disappointed for the travelling supporters because you want a cup run, I just felt that our levels come off it a little bit," he said.

"When you're working at intensity levels to stay at the top of the league, week in, week out and you get this little game where if you come off it five per cent, which I think we did, even though we should've easily won the game, it can cost you and it cost us today."

With a rescheduled league game at Wimbledon to come on Tuesday, Wellens admitted he had probably tinkered with his side too much.

But he felt O's still had more than enough in their locker to have secured progress, adding: "I pick every single team to win. We picked a team to win. I know we made changes but we picked a team to win and what we've seen with the evidence, we should win the game.

"Little things went against us. Fact of the matter is we didn't defend a near-post cross and we let a striker get across us and we get beat 1-0. Worst-case scenario we should be leaving here 0-0 and we've got a replay.

"I probably made too many changes, but we've got Wimbledon from the Queen's death put in, so my thinking has to be to the Tuesday as well as this Saturday.

"Moncs needed the minutes because he's not trained for a while, not played, and Jordan [Brown], Shad [Ogie] needed a game, because if we get anything wrong with the centre-halves he needs to be able to play and he's got minutes under him."