The 28-year-old midfielder joined the Swans from Las Palmas in an £11million deal in the summer, but has made just three Premier League appearances, including a solitary start.
“I have to be honest and say that adaptation period is over," said Clement when asked about Mesa ahead of Saturday's meeting with Bournemouth.
“We're into November and he, as well as the other players, will be picked on merit.
“Clearly because he hasn't played, probably his confidence is a bit low. Even on a subconscious level, confidence is a bit low.
“Yesterday I didn't see him so good in training. Today, I saw him really good. When I see signs of consistency, the player, or a player, will get his chance."
Meanwhile, Clement insists Mesa is not for sale.
“There is no news, he trains every day, he is motivated and pushing hard. I am looking for solutions and he has as good a chance as anybody. He needs to keep pushing," said Clement.
“What the fans have to understand is I see the players every day and based on what I see and what I think is best I pick an XI. When you do that, there are 12 or 13 players not put there.
“Roque has been one of those and there will be the same number this weekend. It's the nature of the role.
“As far as I am concerned there has been no contact from Malaga. It is still November, we want to use the squad the best we can to get the points we need."