Manchester United defender Luke Shaw appeared to mock former team-mate Romelu Lukaku after Inter exited the UEFA Champions League on Wednesday (AEDT).
Lukaku's 12th goal of the season for Inter in all competitions was not enough to prevent the Nerazzurri losing 2-1 to a much-changed Barcelona team at San Siro.
The result, combined with Borussia Dortmund's 2-1 win over Slavia Prague, meant Inter finished third in Group F and will therefore drop into the Europa League for the rest of the season.
Shaw was quick to poke fun at Lukaku on social media after the match.
Responding to a post from the striker back in October, showing Lukaku smiling in training with the caption "UCL", Shaw said: "Welcome back."
Lukaku, who left United to join Inter for a reported initial fee of €65 million (A$105 million) in August, could now face his former employers in the last 32 of the UEFA Europa League.
United have qualified from their group but must avoid defeat to AZ at Old Trafford on Friday (AEDT) in order to secure top spot and enter Monday's draw as a seeded team.