Martin O'Neill reveals Celtic priority transfer position and lifts lid on talks with wantaway player

Engels’ move to West Ham was confirmed last weekend for a fee of £22 million. He nearly left for Nottingham Forest at the start of February, only to help Celtic land a domestic double. But with his stock remaining high and his desire to move to England, O’Neill’s hand was forced.

The manager explained that Engels did not want to risk injury denying him a chance of lucrative move having watched teammate Alistair Johnston’s chances of a summer switch to Everton falter due to an knock picked up against Kilmarnock earlier this month. His departure leaves O’Neill light of options in midfield for Wednesday’s Champions League play-off first leg against LASK, with Alex Oxlade-Chamberlain also suspended.

O’Neill will have to turn to recent signing Mika Baur, Luke McCowan or the unsettled Reo Hatate - who has turned down a move to clubs on the continent - to play alongside captain Callum McGregor.

Asked if he attempted to persuade Engels to remain for this Champions League qualifier, O’Neill said: "We did. He had his mind made up, that's what he wanted to do. I think then it really came home to him.

"In fairness to the lad, he played in the [league] games. He played in the two matches, let's give him credit for that. I think when Alistair got injured, I think he thought, it could happen to him and that chance to not play down in London, and West Ham are a big club who can afford to take him.”

O’Neill believes Celtic will miss Engels’ energy and physicality - and is actively seeking a similar box-to-box midfielder. “That'd be very important for us,” he said. “You can't lose that from a side because you want to keep the dynamic up.”

It was put to O’Neill that with the approach in the winter, Celtic have had months to prepare for Engels’ exit. “I will understand any arguments put forward about that,” said the manager. “If I was looking at it from a distance, ideally it'd be great [to have kept him], and really, I suppose, Arne, from January, surely then his stats and all that type of stuff would become relevant therefore he would have been high on someone's [list].

“I'm not saying you're hoping it'll lie down, and in fairness to us, we've actually actively been looking at replacements for him, they just haven't materialised at this minute. Sometimes that happens.

"OK, so we stop him from going, we play, and he plays the game and let's say his mind is elsewhere, that becomes a problem. That's the thing. But I also take your point and you can argue it anywhere you want that maybe we should have had a replacement in.

“I've tried as much as possible to get a bit of quality in. So, we've let X number of players go and we haven't replaced, numerically speaking. We have a bit of quality in, but we've got a little bit of time. But yes, for the Champions League, I'll take your point.”

Baur could make his European debut just days after signing from Paderborn. "He's a different type of player [to Arne],” added O’Neill. “He doesn't have the same make-up as Arne. When we were taking him in, that wasn't what we were thinking about.

"He's a nice little footballer, he's very competitive, there's not a great deal to him. Regardless of what happens in these two games, we'd want an Arne-type replacement in our team. Someone who is box-to-box.”