Manchester United defender Luke Shaw appeared to mock former team-mate Romelu Lukaku after Inter exited the Champions League on Tuesday.
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", the acronym for UEFA Champions League, Shaw said on Tuesday: "Welcome back."
Lukaku, who left United to join Inter for a reported initial fee of €65million in August, could now face his former employers in the last 32 of the Europa League.
United have qualified from their group but must avoid defeat to AZ at Old Trafford on Thursday in order to secure top spot and enter Monday's draw as a seeded team.
If they do not, they could be drawn against Inter if Antonio Conte's side end up as one of the four best teams from the total of eight to drop out of the Champions League.
Inter are presently the third-best of the third-place teams, behind Ajax and Salzburg, with the remaining four groups to be completed on Wednesday.