The 30-year-old has been linked with a shock move to the Red Devils in the current transfer window after his brilliant 2018-19 Premier League season.
Aubameyang scored 22 goals in the Premier League last term to finish at the top of the goal-scoring charts alongside Mo Salah and Sadio Mane.
Manchester United has been touted as a potential destination for Aubameyang amid uncertainty surrounding Romelu Lukaku’s future at Old Trafford.
The Red Devils have been the busiest top-six club in the summer transfer window so far after adding Daniel James and Aaron Wan-Bissaka to their ranks.
However, former Arsenal goalkeeper Lehmann isn’t worried about reports linking Aubameyang with a controversial switch to Manchester United this summer.
“If you finish fifth [in the league] you can sell players,” Lehmann told DAZN, as quoted by Metro.
“If he was to go to United, a new player would come in who could do better. Arsenal’s goal shouldn’t be to finish fifth or sixth.”
Arsenal signed Aubameyang in a club-record £57m deal from Bundesliga outfit Borussia Dortmund in the 2018 January transfer window.
The African centre-forward has netted 41 times in 65 games in all competitions since his big-money switch to the English capital.
The Gunners lost 4-1 to Chelsea FC in the Europa League final last term to deny Aubameyang his first trophy as an Arsenal player.
The north London side have only signed Brazilian teenager Gabriel Martinelli in the summer transfer window so far.
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