"He has a very good physical condition", Emery said after Saturday's match.
Arsenal haven't kept a clean sheet on the road in the league all season, although when Emery was questioned about this, he didn't seem phased.
The 22-year-old winger was one of the standout performers in Arsenal's 2-1 win away to the Premier League basement dwellers, with the Hale End academy product bagging his third goal of the season in the league.
After losing their first two league games to champions Manchester City and Chelsea, Unai Emery's reign as Arsenal manager went smoothly and they did not taste defeat again until December 16 - a run of 22 matches unbeaten in all competitions.
Deep into injury time on Saturday, Adama Diakhaby broke clear on goal, lifted the ball over Bernd Leno and watched as Sead Kolasinac turned into his own goal via an unfortunate deflection. "I will keep working and trying to do my best for the team".
Chelsea played Manchester City and the gap to Manchester United is one point, so everything is possible. If we ask is it easy or hard, it's hard.
Henrikh Mkhitaryan and Alex Iwobi will support the centre forward, with Alexandre Lacazette filling the said position.
"Our motivation is very great, every player wants to win every match".
Arsenal now have back to back Europa League matches against BATE Borisov before Premier League action returns in two weeks.
And they certainly tried, and in fact had more possession over the 90 minutes at 55%, and the sad truth is that that they were let down by the lack of finishing and confidence in front of goal.
"Knowing we need to take the regularity at home and away, and today this victory I think can give us confidence and the possibility to continue our target in the Premier League".