The north London side head into the game looking to overturn a 2-0 first leg deficit after their defeat at Emirates Stadium last month.
Arsenal were dumped out of the FA Cup by Watford on Sunday and have now only won one game in their last seven outings in all competitions.
However, Messi is wary of the threat posed by Arsene Wenger’s men and says that Alexis Sanchez is one of the key men they will have to look out for at Camp Nou on Wednesday.
Messi is quoted as saying by the Daily Mail: “Arsenal have players more than capable of scoring goals.
“We have put ourselves in a very good position to progress and to reach the quarter-finals but none of the players are thinking that the job is finished.
“Of course we know the danger that Alexis Sanchez can bring but that is only one of many top quality players they have. The style they play is the most similar to that which we play at Barcelona and for that we have a lot of respect for them.”
The Gunners have a mountain to climb heading into the return leg after Lionel Messi’s late double in the first leg gave Barcelona a 2-0 victory in north London – the fourth year in a row Arsenal have lost at home in the round of 16 first leg.
MORE: Man United latest news
MORE: Arsenal latest news
MORE: Chelsea latest news
MORE: Liverpool latest news