London - Theo Walcott believes Arsenal's first-half form has been the key to the club's change in fortunes since the turn of the year.
Arsene Wenger's side travel to face Crystal Palace on Saturday looking for their eighth victory in nine games since the defeat at Southampton on New Year's Day.
That run, blemished only by defeat at Tottenham two weeks ago, has fired up the Gunners' top four challenge and earned an FA Cup quarter-final meeting with Manchester United.
A feature of Arsenal's recent form has been their ability to conjure an early goal that has allowed them to take a grip on the game.
Last weekend it was a double strike from Olivier Giroud midway during the first half that effectively killed off Championship club Middlesbrough in the FA Cup fifth round.
And England winger Walcott maintains Arsenal's ability to work up an early head of steam has helped generate belief within the side.
"The confidence has come from the way we are starting games," Walcott said.
"The manager has put in our heads that we need to start well, particularly from the front and pressurise the ball well.
"You need the fans behind you so getting that early goal settles them and the players down.
"We have maybe been working a lot harder in training. I don't know if that's the reason, but everyone relates to each other and knows their weaknesses and positives. It is working well."
Walcott credits the improvements made at the back with helping move Wenger's side up to fifth place, a point behind fourth-placed Southampton going into the latest round of matches.
"Keeping clean sheets will mean we win games because we always know we are going to score goals and we've continued to do that in recent weeks," he said.
"Things are paying off for us at the moment so we just need to make sure we take it into the next few weeks."
Wenger's team will be boosted by the return of England midfielder Jack Wilshere for the trip to Selhurst Park.
Wilshere returned to full training last week after damaging ankle ligaments against Manchester United in November and is expected to take a place on the bench.
But Aaron Ramsey, Mikel Arteta and Mathieu Debuchy are out, while Alex Oxlade-Chamberlain, Mathieu Flamini and Hector Bellerin are doubtful.