The sight of Darren Fletcher leading Scotland out against Czech Republic on Saturday will warm hearts in certain parts of Manchester, just as it will at Hampden Park.

The Manchester United midfielder, beset by a serious and thus far unexplained virus, has completed only one full competitive match since the game against Chelsea on 1 March. It was in that month that Fletcher's symptoms started.

Fletcher has denied he ever feared for his career but explained the scale of his illness at its worst. "I was in bed, stuck in bed for two weeks," he said. "I had a bad virus, a stomach infection, a combination of things that had a domino effect and put me out for longer than expected.

"The biggest thing was the weight loss. I lost close to a stone which for someone like me – I don't have a stone to lose – was massive. That has been the biggest thing, building my strength back up and putting my weight back on was a real struggle which prolonged it and make it even more difficult to get back."

The Czechs may become victims of Fletcher's hunger on Saturday. His first outing of this season comes at a crucial time with Scotland needing victory to prolong their hopes of a place at the European Championship finals.

"I think my plan was always to be back involved at the beginning of the season for Manchester United which, fortunately, I am," Fletcher added. "I am in the United squad but it is just that the form of the team is so good at the moment that the manager is not changing things. I am fine. Raring to go."

Craig Levein has never had second thoughts about selecting the 27-year-old. The Scotland manager credits Fletcher with improving the professionalism and attitude of a national squad which had lost its way under George Burley.

"He is the best he has been for a long, long time. It's no gamble, he is in great shape," said Levein of Fletcher. "He is our captain and even though he has not been with us the last few games his behaviour and his values are the benchmark for the rest of the team.

"Look at training. It's professional, everyone is always ready in time, there is no messing about. When there is work it's work – it's like a switch goes on saying, 'that's us working now'. That's his mentality and it's rubbing off on other players.

"In the first training sessions I had in this job there were guys kicking balls about all over the place, not listening, turning up late for meetings and you almost felt they were doing us a favour by turning up. Now the role model is Darren Fletcher."

Still, Levein knows his positive sentiment will be useless if Scotland fail to beat a Czech team who are missing the influential Petr Cech.

Scotland's progress has been apparent during the last 12 months – the bulk of their team now play in England's top flight – but, for the manager, tangible proof is needed. After the Czechs, Scotland face a meeting with Lithuania on Tuesday while visits to Liechtenstein and Spain will follow next month.

"It'll all be decided for me as a manager by what happens in the next match," Levein said. "I'll be judged on results. [But] I firmly believe we're capable of winning all or our next three matches. I can't guarantee it, but we're ready. All the ducks are in a row.

"I can't account for what the opposition are going to do but I know that we're ready to play. I couldn't have got the players to this position any better than they are at this minute in time.

"We have a group that is fit, focused and ready to play. There's a great harmony in the team. Those things make me sit here and talk with confidence."

Scotland (4-1-4-1): McGregor; Hutton, Caldwell, Berra, Bardsley; Adam; Brown, Fletcher, Morrison, Naismith; Miller.

Czech Republic (probable 4-2-3-1): Lastuvka; Pospech, Hubnik, Sivok, Kadlec; Hubschman, Jiracek; Petrzela, Rosicky, Plasil; Baros.