Tottenham sent Gil on loan to Valencia in the January transfer window and are looking for the winger to play as many games as possible ahead of returning to north London in the summer.
He suffered an injury for Valencia last weekend and though scans earlier this week showed no serious problem, Gil has been unable to complete a training session today.
According to Spanish daily Mundo Deportivo, Gil could not complete the session, likely due to the discomfort caused at the weekend.
The winger suffered a blow to the hip against Cadiz and had to come off the pitch.
It remains to be seen if a hip issue has flared up during the training session and whether Gil can be involved on Monday.
Valencia are due to play Rayo Vallecano away from home in La Liga on Monday night.
Tottenham landed Gil last summer in a deal which also took Erik Lamela to Sevilla, but he struggled to adapt to the Premier League.
