Swindon boss Paolo Di Canio refused to speak to the press after seeing his side draw 0-0 at Hartlepool.
The Italian's disgust was obvious as he watched summer signing Tommy Miller blast a 71st-minute penalty high over the bar.
Di Canio was still imitating Miller's kick in the dug outs 10 minutes later as his side failed to get their season off to a winning start.
He left skipper Alan McCormack to admit: "It's two points dropped, a disappointing game. A bad day all round, a terrible day. If we want to win the league we have to come to Hartlepool and win.
"We got a good telling off in the dressing room. The manager has high standards and we didn't match them. Sometimes it happens to one player, this time it happened to the whole team. So we get back on the training ground on Sunday, watch the DVD and see our mistakes."
The penalty came after Peter Hartley handballed in the area and Miller, who also missed his last spot kick, for Huddersfield in the League One play-off final last season, missed the chance to sink his former club.