Shanghai (AFP) - Arsenal were outplayed for long periods by Bayern Munich before salvaging a last-gasp draw and then winning 3-2 on penalties in a Shanghai friendly on Wednesday.

Reserve goalkeeper Emiliano Martinez was the unlikely hero for the Premier League side, saving Juan Bernat's soft spot kick after Arsenal substitute Alex Iwobi made it 1-1 right at the end of normal time.

It may have been a friendly and Arsenal emerged victorious, but it made for painful viewing at times for manager Arsene Wenger, whose side suffered a 10-2 aggregate drubbing to Bayern in last season's Champions League.

Robert Lewandowski needed just nine minutes to fire Bayern ahead from the penalty spot as the German champions dominated before Iwobi headed in at the death.

Both sides fielded a mixture of first-team regulars and reserves, with new Bayern signing James Rodriguez and new Arsenal striker Alexandre Lacazette starting.

Arsenal face Chelsea in Beijing in their next warm-up game at the weekend, while Bayern play AC Milan in Shenzhen, southern China.

The German champions will be in Singapore from July 25-29 for the International Champions Cup (ICC).