Bastianini scored his first Sprint victory on the classic British circuit with a well-executed ride from the outside of the front row.
The factory Ducati rider charged into second on the opening lap, settling in behind early leader, Pramac’s Jorge Martin.
On the fifth lap the Martin/Bastianini battle became more significant when fourth-placed Bagnaia dropped his Ducati at turn 4.
In that moment the series lead changed hands with Martin suddenly holding a two-point advantage over the sidelined Bagnaia.
It was a short-lived lead change, though, Bastianini sliding past Martin less than two laps later to take a lead he would hold until the end.
That not only marked Bastianini’s first Sprint win of the season, but ensured Bagnaia retains a single-point series lead heading into the British GP tomorrow.
“I’m very happy, it was a very good battle with Jorge, we pushed on the limit,” said Bastianini. “All of the Sprint [race] has ben crazy. I’m so happy.”
Martin was second, just over a second behind the winner, while Aleix Espargaro – who stunned in qualifying to take pole – came home a solid third.
Fourth place proved to be a tricky position, with two title contenders crashing out from that very spot.
The first was Bagnaia, before Marc Marquez low-sided out of a very comfortable fourth at turn 16 just two laps from the flag.
That left KTM’s Brad Binder in fourth followed by KTM stablemate Pedro Acosta, the pair having clashed early in the race.
Alex Marquez finished sixth followed by Jack Miller, Maverick Vinales, Fabio Di Giannantonio and Miguel Oliveira.
Wildcard starter Remi Gardner finished 18th on his Yamaha.