The 70-minute behind-closed-doors friendly at Hotspur Way, which finished 1-1, turned into anything but a routine pre-season workout after a flashpoint involving Getafe's Mario Martín.
Tonali, who joined Tottenham for £100m from Newcastle this summer, had beaten Martín to the ball and shoved him to the turf, only for the Spaniard to retaliate with a late lunge as the Italian attempted to play the ball forward. Furious, Tonali chased his opponent down, grabbed his shoulder to turn him around, and pushed him several times, including once to the neck.
Several Getafe players rushed towards the scene along with the approaching referee, while Andy Robertson shoved Kiko Femenía away as the Spaniard attempted to remonstrate with the official, with Jan Paul van Hecke and Archie Gray also stepping in to help calm the situation.
Van Hecke, who joined Spurs from Brighton in a £52m deal this summer, was scathing about Getafe's approach afterwards.
"Sometimes it's good to have a physical game. I thought today was a bit too much. From their side, sometimes it's not necessary, especially in a friendly," he said.
"I think in a normal game maybe they have two or three red cards. But that's also maybe the way they play. We knew beforehand they can do it.
"It's a friendly, so you think maybe they would do it a bit less. But on the other hand, we also need to be at our best because if you don't put your foot in, they're going to win it. If that's what the game asks, then you need to put your foot in and battle with them, otherwise they win the battles.
"That's what you don't want. It's one of the first things you need to win in football. You saw at times it got a bit heated, but that's because of the reactions. If you get kicked, you're going to react."
Getafe, managed by José Bordalás and long known for a physical, combative style, took the lead in the 66th minute when Alberto Risco volleyed past Antonín Kinský, only for Conor Gallagher to level moments later with a neat finish following a good run.
Richarlison went closest to a winner late on, but David Soria kept out his header to preserve the draw. Both sides had chances in a goalless first half, with Lucas Bergvall's effort the pick of Tottenham's attempts and Archie Gray doing well to block a drive from Ebrahima Drammeh.
Roberto De Zerbi made no changes across the 70 minutes, which were played with barely a break at half-time, as several senior players also featured in a separate training match at the club's base on Saturday; six young substitutes plus goalkeeper Guglielmo Vicario were named but not used.