ARSENAL striker Olivier Giroud headed a late winner as the Gunners ended a run of two Premier League defeats with victory over a stubborn West Brom to climb back to third.
Giroud was making his first league start of the season and looped in an 86th minute header from a Mesut Ozil cross for his goal.
Until that moment the Gunners had enjoyed nearly 80% possession, but had struggled to find a way past inspired Baggies keeper Ben Foster.

He pulled off a number of key stops, including a double save when he parried an Alex Iwobi shot and blocked the rebound at the feet of Alexis Sanchez.
The 33-year-old former England keeper also tipped over a fizzing shot from Sanchez before West Brom nearly snatched a goal, with Claudio Yacob skying his shot over the bar after Arsenal keeper Petr Cech dropped a corner.
But Giroud finally broke the deadlock to keep Arsenal nine points behind leaders Chelsea, who beat Bournemouth.

Arsenal had buckled in defeats by Everton and Manchester City in their previous two games and the focus was on how they would respond against one of the more resolute teams to beat in the top flight.
It seemed like they were still feeling the impact of those losses as they had just one shot on target in the first half, but they managed 10 after the break as they increased their intensity and urgency.
Sanchez was their main threat as the Chile forward tried to drag the Gunners single-handedly to three points but, like his team, he found himself being continually frustrated.
Sanchez seemed set to score when he evaded a number of defenders in a run across the six-yard box only to strike his shot against the post, before Arsenal’s persistence was eventually rewarded through Giroud.

“It has been a big relief,” said the France striker. “We pushed to the end, kept believing in our game.
“We were very strong altogether and showed a good strong mentality. It was very important to win. We have shown big mental strength.”
West Brom keeper Foster said the defeat was “tough to take” for the Baggies as they were again undone by a late goal, having been beaten in their last away game at Chelsea by a 76th minute strike.

Arsenal’s goal came even later, when the visitors were in sight of securing a point to show for their disciplined and determined defending.
Foster, who signed a new deal with the club just before Christmas, can feel the most hard done by, as he made 10 saves but still ended up on the losing side.
“It is disappointing to lose any game, but to keep Arsenal at bay for so long and then lose with a few minutes left it is horrible,” said Foster.
“You know you’re going to come here and, as a keeper, you’re going to be busy. The lads in front of me were brilliant. But fair play to Olivier Giroud – it was a great header and a great goal.”