Monday’s briefing: Man Utd exit FA Cup but Arsenal still fighting on four fronts

Managerless Manchester United’s season took another turn for the worse as they were knocked out of the FA Cup by Brighton on Sunday.

Arsenal continue to challenge on four fronts after they came from behind to beat Portsmouth 4-1 with a Gabriel Martinelli hat-trick while Scottish Premiership leaders Hearts claimed a crucial 1-0 win at Dundee.

United’s whirlwind week ended on a low note as Danny Welbeck helped shoot down his former club at Old Trafford.

Welbeck was on the scoresheet as Brighton won 2-1 in the FA Cup third round, compounding United’s woes after manager Ruben Amorim was sacked last Monday.

Welbeck added to Brajan Gruda’s opener to put the Seagulls on course for a first victory over United in the competition.

Benjamin Sesko’s header gave United, under the caretaker charge of Darren Fletcher, late hope but Red Devils teenager Shea Lacey was sent off soon after and Brighton held on.

Gabriel Martinelli hit the headlines for the right reasons by scoring a treble as Arsenal overcame an early scare to thrash Championship strugglers Pompey 4-1 in their third-round tie.

The Premier League leaders fell behind less than three minutes into a rain-soaked contest at Fratton Park when Colby Bishop finished from close range.

Andre Dozzell’s own goal quickly levelled the contest before Brazil forward Martinelli struck either side of Noni Madueke’s penalty miss.

Martinelli, who was widely criticised for attempting to push the injured Conor Bradley off the pitch during Thursday’s goalless draw with Liverpool, completed his hat-trick in the 72nd minute.

Taty Castellanos scored an extra-time winner as West Ham avoided an embarrassing FA Cup exit by edging past QPR 2-1.

The Argentinian was brought in for £26million from Lazio