Manchester United have a spy in the camp at Olympiakos, but he's not a very good one.
Northern Ireland international Roy Carroll played 49 games for Sir Alex Ferguson's side after a dream move to Old Trafford from Wigan in 2001, but leaning back on a sofa in the lounge of the Greek club's training facility, where he is still sweating from a session with the goalkeeping coach Alekos Rantos, he is not being very forthcoming: "I can't say that, I'm trying to get another contract here! I'm not going to be giving information away. Ask the manager."
And in that distinctive County Fermanagh accent softened by almost 20 years of life outside of Northern Ireland, he shouts at passing fitness coach Jose Vallejo: "Jose what's happening here? They are trying to get information out of me," before finally offering up: "Listen, we play six up front."
The face is lived-in and the grin is as wide as the goalmouth at Olympiakos' Georgios Karaiskakis Stadium. Carroll will not be in that goal tonight because he is now well down a pecking order topped by the brilliant young Spanish goalkeeper Roberto, whose performance against Benfica helped send Olympiakos through to the knockout stage.
However, he does still wear the No. 1 jersey and most importantly, he is still standing having survived the demons of drink, debt and depression.
"I got my chance in 1995 with Hull City and I grabbed it with both hands. It's 2014 and I'm still here," he says in the build-up to the arrival of his former team.
United are in a similar place to where they were when Carroll joined them – needing to rebuild after the loss of someone who seemed irreplaceable.
Between Peter Schmeichel and Edwin van der Saar, who arrived in 2005 six years after the Dane quit, Ferguson fielded 10 keepers, Carroll among them.
"Peter was the greatest keeper in the world and when a new keeper came in they were under pressure immediately because the fans wanted another Schmeichel," he said.
"Now I read that Patrice Evra is leaving and Nemanja Vidic and maybe Rio Ferdinand, but Wayne Rooney has signed and they have Robin Van Persie – and Juan Mata will be a big boost for next year – but for now it does look as though the only way they will get into the Champions League is by winning it."
They must also do that without Ferguson, who signed Carroll. "He was the father figure," the keeper says. "And not just to the players, but to all the staff. Four years of my life I spent watching him and it was fantastic; he didn't take the training, but when he spoke you listened."
Carroll joined United on the understanding he would be Fabien Barthez's understudy. This team is built on the hope that David de Gea, still only 23, will develop into Van der Saar's equal.
"Age doesn't matter in that sense," Carroll says. "You listen to Roy Keane and he never kept his mouth shut. I was 23, 24, but everybody is equal on the pitch. You don't think 'Oh, I'm 19 I have to keep quiet'. Cristiano Ronaldo came on when he was 18 and he took over Old Trafford."
Carroll's troubles started back in 2006 when drinking, gambling and depression took hold while he was laid up with a back injury – a year after leaving United for West Ham.
"I had an injury like I had never had before and I was out for six or seven months with thoughts that my career could be over. And I got depressed. I didn't help myself by not coming out and talking about it until four or five years later. I went for rehab, my attitude was 'I'm going to help myself' but it didn't work out.
"Three years later I nearly lost my family because I was drinking too much and I said, 'right what am I going to do? Keep on doing what I'm doing and kill myself in two or three years, or be with my family?' And that pulled me out of it."
Does he feel that there should have been more support around him as he began the downward spiral? "I was someone who kept things to himself and just thought 'I'm a tough Irish man' but no man is strong enough when faced with depression."
The problems led to him leaving West Ham and later Derby County before trying his luck in Denmark, but the difficulty of relocating wife Kerry, son Jordan and daughter Ellie meant he had to come back to England.
A call from an agent then led to trial with OFI Crete. Was he not tempted to give up on chasing long shots?
"Not when you're getting a free holiday" he jokes. "The whole family came out to Crete and it worked out. Then Olympiakos came and bought me five months later.
"I had two or three really bad years. I was concentrating on going out and having a good time and not concentrating on my football, but coming to Greece has help me change my life."
So back to Carroll's reluctant job as United's Olympiakos expert. What kind of atmosphere awaits them tonight? "European nights are crazy" he says. "The fans don't have much money to go to home games all the time but Champions League are scary nights.
"The main thing is to try to keep a clean sheet at home and if we can get a goal then terrific. But we want to go to Old Trafford still in the game."