Arsene Wenger was relieved that Arsenal took control of Sunday's Premier League clash against Manchester United to win 2-0 after making a slow start.
Arsenal headed into the game needing a win to keep their hopes of a top-four finish alive, but Petr Cech had to be alert with fine saves from Anthony Martial and Wayne Rooney as the Gunners' defence initially seemed to struggle in the new-look 3-4-3 formation.
But Arsenal regained their composure after the interval, and blitzed United with two goals in three minutes from Granit Xhaka and Danny Welbeck to seal an important win in the race for Champions League qualification - especially after a dispiriting north London derby defeat at Tottenham last weekend.
The win also marked Wenger's first against Jose Mourinho in 13 league attempts, and the French coach said after the game: "We needed to be patient. I felt that if we went in at half-time at 0-0 we would have a good chance to win the game.
"We started a bit nervous, a bit under pressure. Slowly we became better and in the second half we controlled the game quite well.
"The first goal (Xhaka's deflected effort off of Ander Herrera) was a bit lucky; the second goal was a great team goal.
"I’m happy for Danny as well. When you play centre forward you know we want goals. Hopefully it gives him confidence.
"It was important [to respond]. We lost at Tottenham, it didn’t happen many times.
"We couldn’t afford to lose today. We won at Middlesbrough, against Man City, against Leicester.
"We had just one blip. It was a bit physical. We look a bit more stable."
Regarding Arsenal's pursuit of Champions League football, Wenger said: "We have a big game on Wednesday night. Southampton is a good team.
"Collectively they play well, with good possession of the ball. We need to recover to win on Wednesday.
"We still have a chance mathematically. We need some help as well from teams around us."
Wenger also joked that Arsenal's top-four rivals Liverpool got a lucky penalty call against Southampton, despite James Milner missing the spot-kick as Jurgen Klopp's side drew 0-0 at Anfield: "I’ve seen the penalty given by the referee. It was very nice."
And as for ending Mourinho's unbeaten run again him, Wenger added: "It’s between two teams at the end of the day. That’s what I make of it."
