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Pioli blamed fatigue as Milan needed an injury-time own goal to secure a point at the Stadio Paolo Mazza on Wednesday with lowly SPAL having played the majority of the contest with 10 men.

Mattia Valoti's close-range finish and stunning long-range effort from Sergio Floccari gave SPAL a 2-0 lead before Marco D'Alessandro was sent off for a reckless challenge on Theo Hernandez.

Milan pulled a goal back with 11 minutes remaining when Rafael Leao stroked the ball home before Francesco Vicari diverted the ball into his own net in added time.

"It is not easy to recover mental and physical energies by playing every three days," Pioli told a news conference.

"But we must do it and do better. It takes all our focus and determination.

"The players are tired but they will recover energy to make a good performance against Lazio, who rested one day more than us."

Milan were much improved after veteran Swedish striker Zlatan Ibrahimovic came off the bench just after the hour to make his first appearance since March.

Although Pioli felt his tactics throughout were unfortunate not to deliver victory as the draw left Milan two points behind sixth-placed Napoli in the battle for a Europa League group-stage spot.

He continued: "Our approach was not wrong, but the game was tough after we made two careless mistakes.

"We had controlled the game and created several goalscoring chances. There was even time for us to score a winning third goal, but we just failed."

Milan striker Ante Rebic had an off night but Pioli refused to criticise the Croatia international.

"He had his chances," he added. "Maybe today he was less brilliant. Fatigue can be felt."

SPAL coach Luigi Di Biagio acknowledged the dismissal of D'Alessandro on the stroke of half-time "affected" his side.

But despite suffering a crushing late blow, he would not give up on his side's survival chances even though they are seven points adrift of safety.

"As long as we are alive, I will believe it until the end," Di Biagio said. 

"Three games await us that will give us a clearer idea of things. We hope to close the gap in the table."