Max Verstappen won Saturday's Sprint race after dramatically passing Charles Leclerc on the penultimate lap.
Verstappen started from the front at Imola before losing the lead to Leclerc following a slow getaway.
But after a frenetic conclusion to the 21-lap dash, Verstappen ruined Ferrari’s homecoming party by fighting his way ahead of Leclerc at the Variante Tamburello to take the chequered flag and pole position for Sunday’s Emilia Romagna Grand Prix.
But there was further misery for Lewis Hamilton after he started 13th and finished only 14th.
Sergio Perez took third ahead of Ferrari's Carlos Sainz, with Lando Norris fifth for McLaren.
Leclerc is now 40 points clear of second-placed Sainz in the standings, with Hamilton 51 points back.
And with the full quota of points available for Sunday’s Grand Prix, Hamilton’s hopes of getting back into this year’s championship fight could be all-but over after just four rounds.
World champion Verstappen secured pole in Friday’s rain-hit qualifying, but the Dutchman was slow away from his marks and the in-form Leclerc took advantage.
The Monegasque, chasing Ferrari's first drivers' world title in 15 years, roared past Verstappen's Red Bull before beating his man into the opening chicane — his move greeted by a chorus of cheers from those supporters dressed in red.
Further back, Hamilton’s getaway was sufficient, but he was soon gobbled up by AlphaTauri’s Yuki Tsunoda and then the Aston Martin of Lance Stroll.
George Russell — in the other Mercedes — also fell back a place from 11th to 12th.
On the first lap, Pierre Gasly ran into the Alfa Romeo of rookie Zhou Guanyu. The Chinese driver ended up in the wall and the safety car was deployed to retrieve his stricken machine.
The race fired up again on lap four and Leclerc mastered the re-start to leaving Verstappen in his wake.
Hamilton was attached to Stroll’s Aston Martin and finally made his way past on lap nine to move up to 14th, but the British driver failed to make any further ground, crossing the line an eye-watering 41.4 seconds behind Verstappen. Russell moved ahead of Sebastian Vettel in the closing stages to take 11th.
Hamilton and his Mercedes boss Toto Wolff were involved in a heated exchange after qualifying here on Friday evening. And the tension inside the Mercedes’ garage is unlikely to have eased after yet another deeply-unsatisfactory showing.
Up front Leclerc looked on course to take the victory, but Verstappen denied the Monegasque by moving into the lead at the start of lap 20 and finished 2.9 seconds ahead of the Ferrari driver.
