The midfielder, 27, was a surprise absentee from the Toffees's matchday squad for their crucial fixture at Goodison Park.
Widespread reports have since claimed Schneiderlin, alongside Kevin Mirallas - who was also absent from the matchday squad - were banished from training by caretaker boss David Unsworth after falling out with coach Duncan Ferguson.
It has been reported that both players were told to head back inside the club's training base, Finch Farm, if they were not willing to train properly, to which the duo decided to take Ferguson up on his offer.
However, Schneiderlin has since taken to Twitter to reiterate his commitment to Everton, slamming the reports as “not true.”
The Frenchman uploaded a picture with the text: “I have seen press stories today about me 'being sent away from training.' The stories are not true.
“I am fully committed to Everton and will continue to work hard for the club and the fans in training and on the pitch.”
Mirallas, 30, had already addressed the situation on Sunday, writing on Instagram: “Thank you for all your messages. It’s a difficult situation for me, but in life there are things much more serious than my personal situation.”
Everton managed to fight back from two goals down to defeat Watford 3-2 and lift themselves out of the relegation zone without Mirallas and Schneiderlin.
The Merseysiders fell behind to goals from Richarlison and Christian Kabasele but Oumar Niasse and Dominic Calvert-Lewin levelled the tie.
Leighton Baines soon converted the all-important penalty which sealed the victory for strugglers Everton, with Tom Cleverley passing up the chance to rescue a point for Watford by missing a spot-kick late on.