SYDNEY - Arsenal 's record signing Alexandre Lacazette scored on debut in the Gunners' 2-0 win over Australian champions Sydney FC on Thursday.

Lacazette , signed last week in a #52.5 million ($68 million) deal from Lyon, came off the bench in the second half to score Arsenal 's second goal before more than 80,000 fans at Sydney 's Olympic stadium. Lacazette side-footed home to beat goalkeeper Andrew Redmayne from close range after skipper Per Mertesacker had opened the scoring for the Gunners in the fourth minute. "It's important that he gets that off his shoulders because you as a striker expect to score, so you could see he was happy," Arsenal manager Arsene Wenger told reporters.

"But overall what we look for basically is to play at a good pace and develop our collective game and for long periods in the game that was quite good for us. "They gave us tough opposition, they tried for every ball and I would say at the end of the day their goalkeeper was man of the match."

Up to Lacazette 's slick finish Redmayne, a one-time triallist at Arsenal , had denied the Gunners with a string of spectacular saves to give Sydney FC an outside chance of snatching a draw against the English aristocrats. The Gunners got off to a dream start when defender Mertesacker latched onto an overhead kick off a corner from fellow German Mesut Ozil to put his team ahead in the opening minutes.

Mertesacker pivoted and let fly to beat Redmayne from close range. Youngster Reiss Nelson was lively down the right wing and troubled the home defence before he tired  late in the half. "All the youngsters did well, Nelson and Joe Willcock had a very strong performance, they are very young, just 18 years old, so that's very promising and they are English as well," Wenger said.