"The left-back place is up for grabs," said Bertrand.
"Even with everyone fit, no one has nailed it down. It's not that now people have got a chance because certain people are injured. Everyone was in contention at the start.
"It's about who really goes in there and grabs it by the scruff of the neck and makes it their own. Hopefully it can be me.
It's a good start to be called up. Hopefully I can go in, concentrate on my football and let it take its course.
"It's good to be back but I'm taking game as it comes. As each game goes by I get fitter and fitter and hopefully get back up to where I was last year and crack on from there.
"It's on everyone's minds with the Euros coming up. Everyone will be vying for a place and looking to cement that for the summer."