If Pep Guardiola wanted to focus on his team's final Champions League group tie on Wednesday night rather than this weekend's Manchester derby, the absence of David Silva here in Ukraine made that rather difficult.

Guardiola confirmed that Silva has not travelled to Kharkiv after feeling discomfort in the win over West Ham on Sunday when the Spaniard's late goal maintained City's remarkable winning run.

The fact that he could not – or would not – specify the problem only added to the mystery surrounding Silva for the biggest Premier League game of the season so far at Old Trafford.

David Silva may not be fit for Manchester City when they travel to face Manchester United

Was Guardiola playing games with Jose Mourinho? City are expected to make wholesale changes for the Group F tie against Shakhtar Donetsk, so Silva will by no means be the only absentee at the Metalist Stadium on Wednesday evening.

Or maybe he was trying to avoid upsetting Napoli. If Shakhtar get a draw against City, they will go through to the knockout stage at the Italians' expense.

Either way, Silva's fitness remains in doubt four days before the Premier League leaders face their neighbours and closest rivals for the title.

'David had problems in the last minutes (against West Ham),' said Guardiola, who flatly denied reports in Spain that City offered a £80million signing-on fee to Lionel Messi before he agreed a new deal at Barcelona last week.

Pep Guardiola revealed his injury fear over Silva ahead of the Shakhtar Donetsk fixture

'We made a test after the game. I don't know if he'll be able to play on Sunday. That's why he stayed to recover in Manchester but the others are all here.'

Pressed on what the problem is, Guardiola added: 'It's something, something uncomfortable he felt in the last minutes before the goal.

'Hopefully he can be fit for Sunday but it was too risky to play him tomorrow.'

City don't need to take any risks. They have already qualified for the knockout stage as winners of Group F, and victory here would make them the sixth team in the Champions League to finish the group stage with a 100 percent record.

The occasion also marks Guardiola's 100th Champions League game as a coach, having already won the competition twice in charge of Barcelona.

Silva has started all-but one of City's games in their route to the top of the Premier League

He continues to play down City's hopes of doing the same even though their scintillating form suggests otherwise. Yaya Toure sat beside his manager at Tuesday's press conference and claimed they are playing the best football in Europe right now.

'Well it's a nice number,' said Guardiola, rather underwhelmed by the 100-game milestone.

'It means you had a lot of games in this marvellous competition. Hopefully I can enjoy it for longer and be manager for a lot more games.

'But you can't compare with Barcelona and Bayern Munich. It's a new history and a new path.

Yaya Toure could be handed a rare start with City having already qualified as Group F winners

'Barcelona won 14 titles in four seasons, we haven't won once here. In terms of results, there is no comparison.'

Shakhtar, meanwhile, may be playing 300 kilometres from Donetsk because of the conflict in Eastern Ukraine, but as many as 8,000 fans from home are expected to swell a 40,000 crowd in Kharkiv.

Some of them will be wearing Zorro masks after coach Paulo Fonseca promised to put one on after the game if his team progresses.

'I think we can call City if not the best then definitely one of the best teams in the world right now,' said Fonseca.

'But if you ask me whether our tactics will work, I'll answer yes. At least I believe they will.'