ROBERTO Martinez is sitting behind the sprawling desk in his office at Everton's training ground, coffee in hand, thinking about Celtic.

He is reeling off his most memorable visits to Parkhead, a ground he says he loves. There was the Valencia game, the Celta Vigo game, the Barcelona game, the PSG game - "no...PSG was Rangers" - and last month Scotland-Ireland. "I love to see the European nights there. It's always a bouncing, proper football stadium. Perfect for European football."

This isn't how the Everton manager usually spends his afternoons. There aren't old posters of his hoops favourites on the walls. He didn't grow up in the little town of Balaguer, Catalonia, during the 1980s contemplating Celtic men like Pat Bonner, Paul McStay and Murdo MacLeod. But it's germane to get him thinking about the club because, a week tomorrow, Uefa could put Celtic and Everton together in the last 32 of the Europa League.

He says all the usual platitudes at first - there are no easy teams at this stage, whoever we get is going to be difficult - before acknowledging that there is a valuable advantage to finishing first in their group stage (Everton finished above Wolfsburg, Lille and Krasnodar with a game to spare, Celtic are definitely through as runners-up). Seeding will mean Everton avoid the four highest-ranked teams who will drop into the competition for finishing third in their Champions League sections. Would he like to face Celtic?

"They are a real, strong force in European football. They would be tough opposition, absolutely. Any team that finishes second in a group has big enough potential to beat you. Celtic? We all know they are supported and how well they travel. Everton against Celtic? I think it would be big."

Martinez, 41 and looking well at that, is one of the Barclays Premier League's most compelling characters. Bright, open and friendly, he is the quintessential modern manager bubbling with energy and ideas, and one or two idiosyncrasies. Before a match he won't eat so that the blood is in his brain rather than his stomach, helping him think.

If he can prove that one of his players has not had eight hours' sleep (maybe if someone has seen him out in a club) he will fine him. Martinez himself has tasted alcohol only once in his life: a glass of champagne on the day he got married to Beth, his Scottish wife.

He will sit in front of a television for hours at home, studying football. Everton finished an impressive fifth last season, above predecessor David Moyes's Manchester United, and were 11th before yesterday's game against champions Manchester City.

Sometimes big figures in English football give the impression they are just being polite when they are asked about Scotland during interviews, just going through the motions and trying not to sound disrespectful. Martinez is the same at first, but then mentions some perceptive little detail or other which proves he really does know our scene. In the course of a compelling hour with him he brings up Queen of the South, Hibs, Stephen Dobbie, Fraser Fyvie, and his former club Motherwell ("Scotland's third force" he says, smiling). The single season he spent at Fir Park might have been only a footnote in his career and life were it not for the trauma of being one of 19 made redundant by the club's administrators, and the joy he found by meeting Beth. The couple have a baby daughter, Luella. "I suppose she is 33% Scottish, 33% English, 33% Catalan."

The Motherwell year had a profound effect on him. "I'm not 50% Scottish, I wouldn't dare to say that, but I do feel very proud of Scotland as a country. It's strange. Obviously I was born in Spain but you travel a lot and there are countries where you somehow feel a special feeling inside and you feel attached to. Scotland is that sort of country. I love spending time there."

Returns to visit Beth's family in Motherwell are frequent. They spend time at Loch Lomond and Martinez has a sly look at the fixture lists so he can fit in an SPFL or Scotland international game while he is here. "I really enjoyed my time playing for Motherwell. I didn't have a successful time, the Motherwell fans didn't see what I was as a player, but I learned a lot. I learned how it is possible to give young players opportunities in big moments and big events. We had a very cosmopolitan dressing room and I found out that Scottish players are characters who can fit in any league in world football and they can be very, very important in group dynamics."

Martinez "has good people" representing Everton for him in Scotland and cannot foresee not having a strong scouting network north of the border. For Swansea City, Wigan or Everton he has signed or used Scottish-born talent like Steven Naismith, James McCarthy, James McArthur, Shaun Maloney, Gary Caldwell, Dobbie and Matthew Kennedy, the young winger currently on loan at Hibs. At 5ft 9in, in his own playing days he was another of those modern Spanish central midfielders reliant on technique rather than height. Naturally the number of short players in the Scotland squad, Naismith among them, is not a problem in Martinez's eyes. "It is interesting. What Gordon [Strachan] has put together is an exciting team to watch and the front four, when you see them playing against Germany and against Poland, are competitive. You need to be outstanding at what you do and then you don't need to be physical. Spain showed the way in the early years with Iniesta and Xavi. These players are not physically strong but when you are sensational in your ball control you don't need to be strong to win it back. But I really, really enjoy watching Scotland. The understanding is great between [Steven] Fletcher, Maloney, [Ikechi] Anya and Naismith. In midfield there are different options: James McArthur, James Morrison, Charlie Mulgrew, Scott Brown. Really good options."

Brown has been with Celtic since 2007. Had events taken another course Martinez could have become his manager. In June 2009, Celtic and Wigan both asked Swansea for permission to speak to him about their managerial vacancies. "I was a Championship manager, really young, 35, something like that. I knew that the Celtic challenge would be really testing because you have to qualify for the Champions League straight away, you have the knock-out rounds and you need to achieve some sort of success in the domestic league and also perform in Europe, which is quite a rare situation to have."

He went to Wigan instead, lured to the club where he had spent his first six seasons as a player in British football. At the time, it was reported that Swansea's £2 million release clause had proved to be decisive: Wigan would pay it and Celtic would not. Martinez, though, says enough to hint that it had been his choice to remain in England.

"I don't like to speak about those things because they can seem a bit disrespectful. Celtic is a huge football club. It's better just to say that we had very good conversations and the only obstacle was probably that Wigan came knocking at the door and at that time I went to Wigan because of the relationship with [owner] Dave Whelan. I always felt that football should be based on human relationships. Dave gave me the opportunity to come to English football and I spent six years as a player. If he was asking me to become the manager there was only one direction I was going." Martinez kept Wigan in the Barclays Premier League in his first three seasons and won the FA Cup in his fourth. Celtic got Tony Mowbray.

Five years later Celtic went for a thirtysomething foreign manager embracing all the modern football philosophies. The qualities which attracted them to Ronny Deila were pretty much what they saw in Martinez in 2009. Did he think his style, and Celtic's, would have married well? "Definitely. I had won the League One with Swansea playing a certain way and starting a philosophy, and we had a very good season in the Championship but I was very flattered by the interest from Celtic. I was very, very impressed by everyone at that football club. It just wasn't to be, even though that was a real example of the way they have as a football club, of being forward-thinking. I always felt flattered and I will always keep that fresh in my memory. They very much share the football values that I enjoy as a manager. But at that moment it probably felt like the wrong time, unfortunately. It would have been a phenomenal, phenomenal challenge."

Martinez in a Parkhead dug-out after all? Over to you, Uefa.

o Part two of Roberto Martinez's interview - on Rangers fans' attitude to Steven Naismith, replacing David Moyes and Everton's reaction since Hillsborough - will be in tomorrow's Herald.