Ruben Amorim criticised Manchester United's "lack of pace" during the first hour of their Europa League victory against Viktoria Plzen.
United went 1-0 down to Matej Vydra's 48th-minute opener and Amorim made three substitutions within the first 15 minutes of the restart.
Marcus Rashford was removed in the 56th minute for Rasmus Hojlund and fellow forward Joshua Zirkzee was hooked five minutes later.
A minute after Zirkzee was replaced, United equalised through Hojlund. Amorim appeared to criticise the lack of penetration from Zirkzee and Rashford, who did not acknowledge the United head coach when he was substituted.
Read more on manchestereveningnews.co.uk