Video - Danielle Collins' reaction after her handshake with Swiatek

The United Cup came to an end on Sunday with the USA's 2-0 victory over Poland, led by their two leaders Taylor Fritz and Coco Gauff.

Before the match, as required by the protocol of this competition, the players of each team must shake hands with their opponents.

But in this sequence, beyond the smiles of most of the players, Danielle Collins' reaction to her handshake with Iga Swiatek is the most striking (see video below).

As a reminder, the American had a disagreement with the world no. 2 at last year's Paris Olympics, getting annoyed at the pace of play imposed by the Pole during the match and accusing her of being "fake" after her defeat.