Matias has made a positive impression during his first season at Hillsborough, after moving from Nacional term.
The winger may have had his injury problems, but his initial impact proved the quality that he has.
Matias made a blistering start at Wednesday, but he has found first-team chances far harder to come by in recent months.
The 26-year-old has started just once September, but he insists that he has no qualms with Carvalhal’s selection policy and he is also very optimistic about his side’s chances in the play offs.
“I am confident about the play-offs,” he said.
“Our team is very strong. If we play together, we are strong and I think that will help.
“Carlos is the best coach for this project. He is a very, very good coach and he loves Sheffield Wednesday. I am happy to play for him.
“He is a nice guy and a good coach. He tries to help every player do better. He has done a lot for me.
“We will be okay when we play any team in the play-offs.”
Wednesday look set to finish in sixth place in the Championship table, although their play off qualification isn’t totally assured.
The Owls need to win one of their remaining two fixtures - against Cardiff City and Wolverhampton Wanderers - to secure their place in the top six.
If Wednesday do reach the promotion deciding matches, then it looks likely that they will be pitted against the team which misses out on automatic promotion, with Middlesbrough, Brighton & Hove Albion and Burnley all competing for the top two spots.