They face Brighton at home on Sunday and you can keep up to date with that game via our match centre.
The Belarusians piled forward and forced Arsenal stopper Ospina into a number of formulaic saves, interlaced by the Colombian's now signature erratic aerial decision making.
BATE goalkeeper Denis Scherbitski blundered in the 22nd when his clearance found Walcott at the edge of the area to score his second with a low shot.
Walcott scored a brace, Holding scored his first goal for the club, Giroud scored his 100th, Marcus McGuane and Eddie Nketiah made their first appearances, and the Gunners secured three points on the road.
It only took three minutes before Arsenal added a third.
Arsenal have won four of their last five in all competitions, but sit 7th in the standings after a slow start which saw them lose to Stoke and Liverpool.
Nonetheless for the neutral Arsenal's early goals rather diluted the spectacle as a serious contest and even when Mirko Ivanic pulled one back for the Belarusians on the half-hour mark one sensed a comeback was never on the cards.
Rob Holding almost had his second goal for Arsenal from another corner but he swung at the ball and smashed his shot off the post.
Olivier Giroud celebrated his 100th goal for the club, with a penalty three minutes into the second half before Mikhail Gordeichuk grabbed a consolation for the hosts in the 67th minute. There was some pushing in the box but it is hard to determine exactly why the penalty was given. "When you play football, the most hard thing is to score goals and he has scored 100 for us", the Gunners boss added. The Frenchman becomes the 19th player to score a century for the North London side.
Borisov got one back only two minutes after a good cross, which Elneny really should have defended better.
The Gunners are now unbeaten in their last three league fixtures and have climbed to the seventh spot in the table with ten points.