LONDON • Theo Walcott says Alexis Sanchez's ability to reproduce the form that terrorised Leicester City holds the key to Arsenal's success in the Champions League.
The Chile winger netted a hat-trick to inspire Arsenal's 5-2 rout on Saturday.
He had not scored for the Gunners since their FA Cup final win over Aston Villa in May. His early-season form had been patchy as he struggled to recover from leading his country to the Copa America title in the close season.
But Walcott believes the former Barcelona star's scintillating display at Leicester proved he is back in the groove just in time for a crucial Champions League clash with Greek side Olympiakos today.
"I am sure he is going to flourish now with many, many more important goals. It has been a long time coming, he knows that himself," Walcott, who netted the first goal against Leicester, said.
"He is a top-quality player and even when he is not scoring goals, he works so hard for us."
Gunners manager Arsene Wenger agrees Sanchez is back to his world-class best.
His side are just three points behind Premier League leaders Manchester United, whom they host on Sunday.
But, before that meeting, the north London side must focus on Europe as they look to revive their Champions League campaign when Olympiakos visit the Emirates Stadium.
The Gunners slumped to a 2-1 defeat in their opening Group F fixture at Dinamo Zagreb.
That loss leaves little margin for error against the Greek side so the pressure will be on Walcott if Wenger once again deploys him as Arsenal's lone central striker.
He impressed in that position at Leicester and, with 12 goals in his last 13 Arsenal starts, believes it was one of his best displays since a serious knee injury last year.
He said: "I have always said I want to play upfront. The manager has had faith in me and I just want to repay him."
Wenger's men have faced the Greek outfit in the group stages in three of the past six Champions League campaigns.
They are unbeaten in eight home games against Olympiakos, winning six and drawing two.
Marco Silva's men started their European campaign with a 3-0 home defeat by Bayern Munich.
Wenger remains confident of progress to the knockout stages as long as they win all three of their matches at the Emirates.
"Mathematically, we can qualify without any problem if we can produce our performances that we want at home," he said.
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