After Chelsea’s 3-1 away win at West Ham United in January 2006, the media wanted to know how our then-manager Jose Mourinho planned to cope with the loss of Michael Essien to what looked like a nasty injury 12 minutes into the match.

The Blues boss directed their attention to the man who had replaced him in the centre of our midfield, Gudjohnsen, declaring that he had resembled a ‘blond Maradona’ that afternoon.

It was the headline-grabbing moment of Gudjohnsen’s deep-lying creative phase for Chelsea, but by then, he had been playing there for almost a year.

For all that we will remember the Icelander as one of the club’s great strikers, his spell in that more withdrawn role was a fascinating departure for one of the most versatile and technically gifted players of the modern era.

Gudjohnsen’s midfield experiment began in a high-stakes game - the League Cup final in February 2005. At half-time in Cardiff, we trailed Liverpool 1-0 and looked out of sorts. It was the first really concerning period of a season that had been largely plain sailing for us.

The previous two games had ended in defeat: first to Newcastle United in the FA Cup, then to Barcelona in the first leg of a UEFA Champions League last-16 tie. It finally enabled the outside world to ask questions of Chelsea – were we capable of responding to this wobble? Had our opponents worked us out?

To answer that question, we have to look at the way we were playing that season. First things first, we had switched to a staggered system, with Claude Makelele sitting deeper than the rest of the midfield, giving us an immediate numerical advantage in the middle of the pitch over teams playing the typical English 4-4-2 system of the time.

After starting with a diamond midfield, and achieving functional, if unspectacular success, Mourinho decided to move to a 4-3-3 system, which could become a 4-5-1 when we were on the back foot. That meant sacrificing a centre-forward and playing with wide attacking players, who could stretch the opposition by going wide and trying to find the lone striker with balls into the box, which was the aim when Didier Drogba played up top.

Alternatively, those wide players could look to run beyond a deeper centre-forward and make the most of his clever touches and through balls, as they did when Gudjohnsen was chosen to lead the line.

The Icelander’s eventual withdrawal into midfield was the result of several combined factors. The first was the unavoidable reality that only one of him and Drogba could play up front at any given time.

Then there was the fact that the third midfield berth, alongside Frank Lampard, in advance of Makelele, was up for grabs. Tiago played there most often in 2004/05, but Geremi and Alexey Smertin also had a look-in early in the season. All of them had done a job, but there was certainly room for a more artistic option.

Finally, there came a time when our opponents began to man-mark Makelele to stop him from picking the ball up from the back four and beginning our attacking moves. To counteract this irritation, we needed an alternative outlet in midfield who was comfortable receiving the ball facing his own goal and turning to kick-start our attacking momentum, thereby taking the onus of the now-occupied Makelele.

Moving Gudjohnsen into the midfield solved all three of those situations quite nicely, completing the tactical solution, as Mourinho explained: ‘If I have a triangle in midfield – Makelele behind and two others just in front – I will always have an advantage against a pure 4-4-2 where the central midfielders are side by side. That’s because I will always have an extra man.

'It starts with Makelele, who is between the lines. If nobody comes to him, he can see the whole pitch and has time. If he gets closed down, it means one of the two other central midfielders is open. If they are closed down and the other team’s wingers come inside to help, it means there is space now for us on the flank, either for our own wingers or for our full-backs. There is nothing a pure 4-4-2 can do to stop things.’

Armed with this insight, let’s go back to the Millennium Stadium on 27 February 2005, where we were behind to a John Arne Riise goal in the League Cup final. Sensing the need for more creativity, more attacking impetus, Mourinho made a couple of brave substitutions.

He took off the functional Jiri Jarosik, who had been making up the midfield trio with Makelele and Lampard, and replaced him with scheming forward Gudjohnsen. On 74 minutes, he withdrew defender William Gallas and brought on another striker, Mateja Kezman, to partner Drogba up top.

It worked. Our pressure produced an equaliser – an own goal from Steven Gerrard, who was rumoured to be on the verge of agreeing to join us at the end of the season – which took the game to extra time, where goals from Drogba and Kezman gave us a 3-2 win and our first trophy under Mourinho's leadership.

‘It worked quite well!’ reflected Gudjohnsen. ‘It’s easy to overlook it because you don’t see my name on the scoresheet, but some of the games I’ve played without goals have been up to a very high standard, and that’s one of them. A lot of people came up to me and complimented me, not just for playing in midfield but for actually changing the game.’

Gudjohnsen had been a revelation in midfield, and he spent much of the rest of the season there, helping to connect the defensive half of our team – the back four plus Makelele – with the attacking half – the front three plus a shuttling Lampard.

‘Frankie and I started developing a good relationship, running off each other,’ he added. ‘I used to fill in when he went forward, and vice versa.’

He was rewarded with his first league winners’ medal to add to the League Cup success a few months earlier, shortly before we overcame the first-leg deficit against Barcelona in dramatic fashion at Stamford Bridge to continue our Champions League run.

‘I enjoyed the deeper role. We had the perfect striker to be on his own up front, which was Didier. We had Makelele, we had Frank, and me in a sort of half-advanced position. I knew Frank made a lot of runs, so I had to be careful I wasn’t too advanced. It worked well. I played in the same position against Barcelona and that worked, so it was gradually becoming my position, as in “I’m a midfielder now”.’

The following season, Gudjohnsen had yet more competition for places. Hernan Crespo and Carlton Cole returned from loan spells to make it four centre-forwards vying for one spot, while Essien added a new element to the midfield alongside Makelele and Lampard. Gudjohnsen was only called upon to reprise his creative role when Essien suffered that injury at West Ham in January 2006.

Yet, despite his starring role in the 3-1 win at Upton Park, capped off with the most beautifully-weighted through-ball for Drogba to score the clincher, Gudjohnsen soon found another new arrival vying for his spot, as Mourinho’s former Porto midfielder Maniche signed on a short-term deal.

It proved to be Gudjohnsen’s final season at Stamford Bridge and he started fewer league games than he had in any of his previous five with the club, beginning just 16 of our 38 Premier League matches as we successfully defended our title.

He moved to Barcelona the following summer, demonstrating not only his technical prowess but also the esteem in which he was held within the game. In total, he made 163 appearances for Chelsea between 2000 and 2006, scoring 78 goals and winning two league titles, the League Cup and two Community Shields.

'Not bad for a boy from a little island up north!' as he put it when he said goodbye in 2006.

Perhaps that goals tally would have been slightly higher had he spent his entire time here as a forward, but then we wouldn’t have had the memories of the ‘blond Maradona’ pulling the strings and carrying the ball between the lines.