Joey Barton has criticised David Unsworth's ability as Everton's caretaker manager and suggested the club took a "shortcut" in promoting him from the U23s.
Barton, who spent time in the Everton academy while Unsworth was a player, also questioned whether the 44-year-old should return to his role as youth-team boss if he does not get the senior job full-time
Unsworth's U23s won youth-league titles and he was promoted after Ronald Koeman was sacked last month, but he has won one and lost five of his seven games in charge, shipping 20 goals in the process.
"Unsworth has been that bad as first team manager, you have to question his credibility in handling U23's again," Barton said on Twitter after Everton lost 4-1 at Southampton, live on Sky Sports.
"(I) told you all what would happen and you chose to focus on the media noise. You can't take shortcuts at this level. This is what happens when you do.
"The manager is responsible. He is the leader. He picks the team. He sets the tone. If the players don't perform, it's on him to find a solution.
"Don't like it? Don't put yourself in a position to lead. Don't say you want the job, if you can't do it. No sympathy."
Unsworth admitted himself at full-time at St Mary's that it was time for the Toffees' hierarchy to make a decision on their next permanent boss - and then hit back at Barton's comments.
"When we start listening to what Joey Barton has to say I think it is time for everyone to go home," the ex-left-back said.