The Gunners were in Europa League action on Thursday evening and played out a 3-1 win over Bundesliga side 1.FC Koln, however boss Arsene Wenger rested a number of regulars.
The Chilean, who was on the verge of joining Manchester City on transfer deadline day, was the star of the Europa League game against Cologne and scored a superb victor. You do not win the [FA] Cup the way we did without it.
It is with this in mind, coupled with the Gunners' atrocious start to the season which has seen them beaten 1-0 at Stoke City and humiliated 4-0 at Anfield by Liverpool, that Merson has selected his combined Arsenal and Chelsea XI for tomorrow's clash at Stamford Bridge. I think they should be alright.
Asked whether the club would need his fighting spirit against Chelsea, Wenger said: 'Yes, but he played at Liverpool as well. We lose all together and win all together. It is not just about one, it's about the team performance. That's everyone who comes on or who starts is giving 100 per cent.
"I believe that, on the day [against Liverpool], everything went against us". We were not sharp physically'. It was three days before the end of the transfer window and some players had their heads in and out. Arsenal have not won any of the last 13 Premier League away games against last season's top-six teams and have suffered defeats on seven of their last eight visits to Stamford Bridge. Francis Coquelin is out with a hamstring problem and Santi Cazorla is ruled out with an ankle injury. But a lack of quality is not permanent.