A big name in Scotland, Stiliyan Petrov was unproven in England when he moved south in the summer but just three months later he is one of the Premiership's players of the season. He tells Phil Shaw about falling out with his country's greatest player, his unusual method of learning English... and how Martin O'Neill persuaded him to sign for Aston Villa

At first glance Stiliyan Petrov is the most uncomplicated of footballers. A genuine team player, a box-to-box, perpetual-motion midfielder who can both win the ball and put it in the net. As a man, he is open and articulate. Yet a conversation with Aston Villa's £6.5m signing from Celtic reveals a career full of tangled emotions and extraordinary episodes.

Last month, for instance, Petrov chose a successful week for Bulgaria to announce his international retirement. The captain of his country, aged only 27, he vowed not to represent them again as long as they were coached by Hristo Stoichkov. The very individual, that is, he continues to cite as his idol.

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On other occasions the quirkiness has been tinged with humour or sadness. Both elements are contained in Petrov's memories of lonely early days in Scotland, when he might have been lost to the fast-food trade. He also talks of the bizarre hotel meeting that brought him south.

Even his first name has a twist. Villa's media department were at pains to point out the "y" in it. But with so many ex-Celts following Martin O'Neill to the Midlands, it is the Scottish moniker immortalised in the title of his recent autobiography, You Can Call Me Stan, that his coaches and colleagues will be shouting when Villa visit Everton today.

The Petrov-Stoichkov saga has enhanced oddity value, O'Neill bucking the trend of managers who rub their hands at the prospect of a key player jumping off the international treadmill. The Northern Irishman urged him to think again. Even his charismatic counsel has changed nothing.

Petrov quit after Bulgaria drew with the Netherlands and beat Luxembourg to remain unbeaten after four Euro 2008 qualifiers. As we discuss the matter against a background of thuds and groans - this is the corner of the Bodymoor Heath training centre where the Villa lads play darts - he hints that the problems run deeper than any personal rift.

"A few things didn't go the way they should have done," he explains. "I said to myself that I should stop here. I'm not doing this to try to get Stoichkov out of a job. I just wanted to show him that a lot of people have interfered, and that he should try to stand on his own feet and try to make decisions for himself and the team."

The irony is that Petrov grew up idolising Stoichkov as the star of the 1994 World Cup side who took the nation's name around the globe. He imagined donning his Barcelona No 10 shirt and fulfilled an ambition when the rookie and the veteran lined up together for Bulgaria.

"Stoichkov was my hero. Still is. He was the one every young person in our country, not just footballers, looked up to. Whenever people find you are from Bulgaria, they make the connection to him. When you have someone like that, you try to follow in his footsteps."

Which makes their estrangement all the more mysterious. "This isn't something I've rushed into. A lot of people expect me to say, 'OK, I'll play again'. But if it's still Stoichkov, I won't. I wish him and the team good luck. They can reach the European Championship finals. But I've made my decision and I won't let myself down on it."

Petrov smiles as he speaks. As proud and patriotic as his post-interview descriptions of Bulgaria's beauty indicate that he is, this issue is not eating him up inside. It might have done when he was younger, but he now has the self-assurance that comes from surviving a torrid start at Celtic and going on to become Scotland's footballer of the year. Perhaps more pertinently, he has the perspective provided by being a husband to Paulina, a former economics student from Sofia, and father to Stiliyan Jnr, aged three.

He is, self-evidently, a stronger character than the teenager John Barnes recruited from CSKA Sofia. Petrov had first played senior football at 15 for his home-town team, Montana, but even the transition from provincial Bulgaria to the capital could not prepare him for the culture shock of the land of the deep-fried Mars bar. "I was 19, confused, and in a strange place where I couldn't communicate. The other Bulgarian who came to Glasgow with me, Milen Petkov, didn't sign. He didn't fancy it. It was a tough few months. That's normal for anyone uprooting to a new country."

What is not normal is to lie on the floor, sobbing and thumping the floorboards in homesickness and loneliness. Petrov feared he was having a breakdown. And his performances were not helping the situation. "John Barnes started me at right-back, where I'd never played. It's hard when you don't understand what your team-mates are telling you about where you should be. Against Motherwell, I made the mistake that cost the winning goal. I sensed the other players weren't happy with me. From that moment I was determined to learn English."

One of the first Scottish friends he made found a novel way to help him with the nuances of the language and dialect. "He had a burger van and encouraged me to work behind the bar because it meant I had to communicate with people ordering food."

Honestly? "Yes! Some of the customers used to stare, thinking, 'That looks like Stiliyan Petrov, but it can't be'. But soon I started to understand things better. It meant I could get involved in the dressing-room banter. That's important because a team is like a family. You can't be a part of it if you're on the outside when people are talking."

Nevertheless, Petrov was still struggling to win over the Parkhead public when O'Neill took over in 2001. "I wasn't playing that often but he said he'd give me a chance to prove myself to him. He told me he could bring in new players, but if I wanted to stay I could do it by playing the way he wanted. I liked the fact that he didn't promise me things he couldn't deliver, like some managers. I got my head down in pre-season, worked hard. He began playing me regularly."

Man-management is crucial to O'Neill's modus operandi. Anyone who has seen Villa's work-rate this season, compared with near-identical personnel under David O'Leary, is struck by how he has coaxed more from them. "He treats people with respect and intelligence," says Petrov. "He understands we're all different characters with different needs. And he knows we need to enjoy our work."

How much more to O'Neill is there than knowing who to kick up the backside and who to put a comforting arm around? "He's very good at analysing things in games and talking you through them later, one to one. And in matches, he keeps things simple. If something is wrong, he tries to fix it in a quick, straightforward way. His assistants, Robbo [John Robertson] and Wally [Steve Walford], are vital to him. They work as a unit. I don't think they can work without each other."

The fortunes of Petrov and Celtic soared in tandem. Medals and titles followed, along with the unforgettable run to the Uefa Cup final and narrow defeat by Jose Mourinho's Porto in Seville. He was no longer "that Bulgarian" but a household name.

"There's no privacy for the Old Firm players. When you go out, you're always asked for autographs and pictures. But you accept that. And the Rangers fans were friendly to me. The most hostility I got was being pelted with snowballs when I went to take a corner at Aberdeen. But that's a good sign. It means you're playing well."

Gradually, though, Petrov came to feel unfulfilled by Scottish football. European combat stimulated him but made it harder to "get up" for playing each SPL side at least four times a season. "A game at Inverness Caley Thistle late last season brought it home. I couldn't get motivated. The spark wasn't there. I spoke to [O'Neill's successor] Gordon Strachan afterwards and he said he totally understood. I said I wanted to leave. He tried to keep me but he knew where I was coming from."

Where he was going to became the issue. "People said I was holding out for Aston Villa, but that wasn't true. Portsmouth made four offers and if Celtic had accepted any of them, I might have been there now." That said, he was delighted when talks progressed sufficiently for him to meet the newly installed O'Neill.

"Martin brought Didier Agathe [a former Celtic colleague who later joined Villa] along to the hotel to say hello. He also told me he had Chris Sutton [ditto] hidden under the bed and Henrik Larsson hiding in a wardrobe. We laughed and it took any tension out of things."

Petrov enjoyed an outstanding debut for Villa at West Ham, drawing praise from Sir Alex Ferguson at the press conference preceding Manchester United's tussle with Celtic. He admits to missing the Champions' League but is not envious of his old colleagues.

"I went to watch Celtic beat Benfica 3-0 and got a great reception. The boys understood it was time for me to move on and test myself against the best. I'd become the longest-serving player, which was ironic because when I arrived it didn't look like I'd stay long."

English football, where "the buzz is like an Old Firm game every week", has not disappointed him, while being among friends has helped him settle without recourse to burger vans. "I'm not lonely here. The big difference from when I came to Glasgow is my family. Paulina is pregnant again but that hasn't stopped her discovering the big shops in Birmingham!"

Nor has "Stan" Petrov disappointed Villa, although the regular marksman in Scotland is still awaiting his first goal. "I know it will come and I'm not worrying about it. Who scores doesn't matter so much as how we do as a team."

They were doing well, too, before running into an in-form Chelsea in the Carling Cup on Wednesday. "We've lost only once in the Premiership. When Liverpool beat us, we gave them too much space in the first half. But we learnt fast. Second half, we were in their faces, and we took the improvement into the win over Blackburn.

"I played against Everton in a pre-season friendly for Celtic and they have some good individuals. But David Moyes has them working very hard as a unit. They showed two seasons ago it's possible for clubs to break into the top four. We can do the same. Why not? European football is incredible and the Villa players want to achieve it next season. I've got used to winning things. I see no reason why I should lower my ambitions now."

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