Arsenal took a huge step towards Champions League qualification with a crucial win over Manchester United in a breathless game at Emirates Stadium.
The Gunners followed up their victory over Chelsea to climb above Tottenham into fourth place and ramp up the pressure on Spurs ahead of their game at Brentford later.
The result surely ends any hopes United had of finishing fourth. They are six points behind Arsenal having placed a game more.
Arsenal flew out of the blocks and were ahead after just three minutes when a shot from Saka was tipped away by David de Gea but only to Tavares to tap in his first Arsenal goal.
There was controversy midway through the first half when United penalty appeals were waved away after Cedric used his arm to block the ball in area. It was a let-off for Arsenal.
There was more controversy when Arsenal doubled their lead on 31 minutes.
Eddie Nketiah thought he had made it 2-0 but the striker was ruled to be offside by VAR. But the VAR official adjudged Saka was fouled by Alex Telles as he poked the ball to Nketiah. Referee Craig Pawson went to the screen and awarded a penalty.
Just like against Chelsea on Wednesday, Saka made no mistake from the spot.
But United pulled a goal back immediately when Cristiano Ronaldo scored from a Nemanja Matic cross.
Both teams had chances at the end of the first half and United then wasted a golden opportunity to equalise when they were awarded a penalty early in the second half.
Fernandes, rather than Ronaldo, stepped up, did a little shimmy then sent a poor penalty off the outside of the post.
Ronaldo then had a goal disallowed for a marginal offside and United were on top before Granit Xhaka hit a blistering shot past De Gea from 25 yards to seal victory for Arsenal.
