Darrell Clarke launched an astonishing tirade at his Cheltenham players and apologised for their “woeful” performance in 5-1 loss at AFC Wimbledon.
Without a win in five Sky Bet League Two games, the Dons made light work of the League One strugglers to reach the FA Cup second round.
Town, who broke records by going 10 games without a league goal at the start of the season, reached new lows in a desperate Plough Lane display.
“It’s nowhere near good enough,” raged Clarke. “At least we are all in agreement in the changing rooms, that’s what it was.
“It’s a woeful, embarrassing performance. Apologies to the fans that came to watch that.
“I have to choose my words very carefully because I am very angry at the minute and I want to make sure I don’t chuck too many people under a bus.
“It’s nowhere near the standards that I will be taking this football club to and the players are under no illusions about what I thought about the performance, and the staff, and now it’s about a reaction.
“It was abysmal, all of it. Woeful. Defensively, we gave them a 2-0 start, we were absolutely miles off it individually and collectively.”
The Robins looked to have turned a corner under Clarke, appointed in late September, beating Carabao Cup quarter-finalists Port Vale and Cambridge in their last three games.
All of that positivity ebbed away as Ali Al Hamadi opened the scoring with a fine finish into the bottom left corner in the 23rd minute after Omar Bugiel’s pass.
Tilley netted his first during first-half stoppage time, touching past the advancing Luke Southwood after Connor Lemonheigh-Evans’ ball.
Tilley volleyed in the third from the edge of the box after 61 minutes before Josh Davison beat Southwood with a deflected effort to make it 4-0 four minutes later.
Lemonheigh-Evans then curled in the pick of the Dons’ goals from 20 yards in the 70th minute.
Rob Street grabbed a consolation before Aidan Keena’s penalty hit the post in the 85th minute to compound a miserable afternoon for the visitors.
AFC Wimbledon boss Johnnie Jackson said: “Great performance. A really good test for us against a team from a higher league.
“Really, really complete performance. We created an awful lot and shut them out for the most part so I have to be pleased with that.
“We could have scored double what we did. We scored five and could have had five more.
“Cheltenham struggled at the start of the season, but since Darrell (Clarke) has come in, they’ve had a real response. They’ve won two out of their last three and started scoring, looking like a good side.
“We weren’t thinking it’d be an easy one for us. They are a league above and they have had that bounce, so we had to be right on and we have to give ourselves credit because we’d have done that to a lot of teams today.”