Arsenal FC kissed this season’s Carabao cup goodbye after losing to Brighton & Hove Albion by 3-1 on Wednesday night.
The Gunners have lost for the second time this season in England after 20 appearances in all competitions.
Danny Welbeck’s first-half penalty kick had cancelled out Eddie Nketiah’s opener, before Mitoma and Lamptey struck in the space of 13 second-half minutes to end Arsenal’s nine-match home winning run.
Julio Enciso headed just off target before Jeremy Sarmiento fired narrowly wide.
But Arsenal struck in the 20th minute when Reiss Nelson found Nketiah, who curled a smart first-time finish past Jason Steele.
Debutant Karl Hein’s slip offered Brighton their equaliser, though, as the goalkeeper brought down Welbeck, who coolly converted his penalty kick into the bottom-right corner.
A fizzing Nketiah right-footed drive cannoned against the left post after the interval, before Steele kept out Nelson’s header with a stretching stop.
Brighton hit the front as Sarmiento danced through the middle before laying off for Mitoma to whip a right-footed effort into the bottom-right corner from inside the area.
Former Chelsea defender Lamptey sealed victory soon after as he drilled under Hein after being teed up by Billy Gilmour.
Chelsea’s disappointing run of form continued as they were eliminated from the EFL Cup by Manchester City at the third-round stage with a 2-0 loss.
Both sides made seven changes to their line-ups for the heavyweight tussle at the Etihad Stadium and it was Chelsea who looked the brighter during the first half.
But after Christian Pulisic and youngster Lewis Hall spurned promising chances, quick-fire goals early in the second half from Riyad Mahrez and Julian Alvarez put Manchester City in control.
Manchester City, who introduced Kalvin Phillips for his first appearance since mid-September, saw out the win to mean an early exit for last season’s beaten finalists Chelsea.
They were restricted largely to shots from range in a first half edged by Chelsea.
The London would have been ahead at the interval if not for some good goalkeeping and poor finishing.
Pulisic scuffed a shot at Stefan Ortega from close range and had another effort from further back saved, while the lively Hall was denied at the end of a good run.
Jack Grealish forced Edouard Mendy into a couple of saves early in the second half, shortly after Phillips’ introduction, and Manchester City’s period on top resulted in the breakthrough goal.
Mahrez was fouled by Trevoh Chalobah just outside the box and he sent the subsequent free-kick over the Chelsea wall —- with Kalidou Koulibaly failing to jump —- and past Mendy.
The hosts doubled their lead five minutes later through Alvarez, who tapped in after Mendy could only push Mahrez’s shot into the path of the Argentina international.
Ortega produced another fine stop to deny Hall, while Pulisic had a late goal ruled out for offside, but Pep Guardiola felt no need to turn to substitutes Kevin De Bruyne and Erling Haaland.
Nottingham Forest produced an impressive performance to knock Tottenham out of the Cup competition with a 2-0 win, even after finishing the game with 10 men.
Second-half strikes from Renan Lodi and Jesse Lingard gave the Premier League’s bottom side victory, though nerves were heightened when Orel Mangala was sent off with 15 minutes remaining.
Spurs have made a habit of dramatic comebacks of late, and Antonio Conte named a strong side at the City Ground, including Harry Kane.
He only made four changes from the team defeated by Liverpool on Sunday.
But they could not rescue a result this time and have now lost consecutive matches ahead of meeting Leeds United in their final fixture before the World Cup.
A quiet first half saw Spurs debutant Fraser Forster called into action to deny Lingard on the rebound after a deflected clearance had struck the post.
At the other end, Wayne Hennessey parried away a fierce effort from Matt Doherty.
Lingard stung the palms of Forster again with a shot from the edge of the box early in the second half.
Just moments later the former Manchester United man found Lodi on the left, with the Brazil international cutting inside onto his right foot and bending an effort into the far corner.
It was 2-0 in the 57th minute when Forest struck on the counter down the right.
Former Spurs man Serge Aurier put in a cross for Sam Surridge to head back across goal, allowing Lingard to nod in his first goal for the club.
Kane made way on the hour for the returning Richarlison, but it made little difference as Forest claimed only their second victory in their last 12 games.
This was in spite of Mangala receiving a second yellow card for a foul on the Brazil World Cup star, who had a goal ruled out late on for offside.