Arsene Wenger has given the reasons why he regularly substitutes striker Alexandre Lacazette.
The Frenchman, who joined the Gunners last summer for £53million, scored on his Premier League debut and played the full 90 minutes in Arsenal's 4-3 win over Leicester.
However since the opening day fixture he has completed a full match just six times out of 27 league matches.
Since the arrival of club-record signing Pierre-Emerick Aubameyang in January, Lacazette appears to be seen as a back-up option as the last time he racked up 90 minutes was against Swansea on January 30.