Everton forward Kevin Mirallas has apologised for his behaviour in a training session last week but rejected suggestions he was disciplined for a poor attitude.
Both the 30-year-old and Morgan Schneiderlin were left out of the squad for Sunday's 3-2 win over Watford after what Press Association Sport understands was an incident at the club's Finch Farm complex.
On Monday Schneiderlin, writing on Twitter, dismissed reports he had been sent home from training on the eve of the game because of a poor attitude and now Mirallas has spoken out, admitting he struggled to contain his frustration after being told he was being left out.
"I have to restore the truth after some articles in the medias," he wrote on Instagram.
"I was not excluded of the squad due to a lack of commitment during training this was a manager Decision And I was frustrated as I am fully committed in Everton since arriving in 2012 and I can't accept our actual ranking....
"I apologize to the president and owner, my team mates and the manager for not being able to cope at that moment with my frustration."
Everton midfielder Morgan Schneiderlin has denied reports he was sent home from training.
Schneiderlin and Kevin Mirallas were left out of the squad which beat Watford 3-2 on Sunday after being involved in an incident at the club's training ground a day earlier, Press Association Sport understands.
It was reported that on Saturday the pair's involvement in a session at the club's Finch Farm complex ended early after their attitudes were questioned by coaching staff.
But Schneiderlin on Monday refuted the suggestion he was sent home and insisted he remains fully committed to the club.
He wrote on Twitter: "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."
Morgan Schneiderlin has emerged as a doubt for Manchester United's Champions League match against CSKA Moscow.
Schneiderlin played the entirety of United's 0-0 draw at Crystal Palace on Saturday but missed the open part of the squad's final training session before their meeting with CSKA at Old Trafford.
Antonio Valencia and James Wilson, who were left out of the stalemate at Selhurst Park through injury, also missed the session at the AON Training Complex in Carrington on Monday morning.
Phil Jones and Memphis Depay also missed the draw in south London on Saturday. They trained separately from the rest of the squad at Carrington.