Former Arsenal star Danny Welbeck has reacted after his current team, Brighton, beat the Gunners 3-0 and all but ended their title hopes on Sunday.
Brighton scored three second-half goals to beat title-chasing Arsenal at the Emirates Stadium.
The Seagulls are sixth with four games remaining, while the damaging defeat may have ended Arsenal’s title dream as they are now four points behind Pep Guardiola’s side.
Manchester City just need to win one of their final three games, and they could clinch the title as soon as next week.
“It is a tough one [for Arsenal to take],” said Welbeck, who spent five years at Arsenal earlier in his career.
“I have a great affiliation with the club, I loved my time here, and everyone’s always given me a good reception when I’ve come back.
“But it’s football, and you have to remain professional, and we’ve done that today.
“It’s not something that happens by luck,” he said.