With the abduction of Mikel's father in Nigeria still unresolved, the manager will take a decision on whether the midfielder starts the game but last weekend's performance was evidence that he can focus fully on the game.
'I have to go with the word my player gives to me and for the game against Stoke, Mikel felt well enough to play,' Villas-Boas says.
'Players that go through major disappointments or personal things in their lives can still be okay to play because they feel well on the pitch. It is the way to avoid the things that are running in their personal lives or to focus on the different things.
'Mikel made himself available for training and selection so I will just judge it like that. I agree he is showing amazing mental toughness.'
It was the manager who first informed Mikel of what had happened in his homeland, a task he says wasn't easy.
'Hopefully this can be resolved as soon as possible,' he adds. 'All of his colleagues are hopeful of that.
'Different players can react in different ways. Some players want straight away to go back to their families, others prefer to be like this and live on day by day, not because they are distant from what is happening but it's their choice.'
The Barclays Premier League enters its second weekend with today's opponents West Bromwich Albion arriving off the back of a home defeat by Manchester United.
'That game told me the same about Man United, the team that won the championship last year,' says Villas-Boas.
'They suffered a few injuries, unfortunately for them, but they are a strong team and one of the favourites for the title. All of the good signs for Manchester United are there.
'Regarding all the first games in the league, there were a couple of surprises but that is nothing new. In the beginning for all the top teams you can have average performances and I would say that about all the top teams apart from Man City, although until the breakthrough of the first goal Swansea had a couple of periods of possession when, without threatening a lot, they were in control of the game.
'You sensed that a breakthrough would take Man City through to a better result. I thought the same about our game. If you unlock one goal it takes Stoke out of their area and you find more spaces and you can go on to a better result but it just didn't happen.
'The Man United game was a good game with chances at either end and it fell in the end to Man United. I think it was even in opportunities for both teams.'
Chelseafc.com