The Belgium international struggled to have a telling impact on the second leg of Chelsea’s last-16 clash at Stamford Bridge as Hazard faced his potential suitors.
PSG midfielder Adrien Rabiot broke the deadlock before Spain international Diego Costa levelled for the hosts ahead of the break.
The reigning PFA player of the year was caught on camera swapping shirts with Di Maria as the players headed for the changing rooms at Stamford Bridge.
Sweden captain Zlatan Ibrahimovic scored a second-half winner to seal a 4-2 aggregate victory for the Ligue 1 champions.
Former Manchester United captain Keane questioned Hazard’s mentality after the half-time incident.
“I’m afraid to comment. This is bad enough at the end of the game, but at half-time in a big game?” Keane told ITV Sport.
“What is a player’s mind sight? A big game and you’re thinking about swapping shirts at half-time. I wouldn’t bother at the end of the game. Shocking.”
Hazard has been heavily linked with a move to Ligue 1 champions PSG over the past 12 months.
The Belgium forward has only scored two goals in 34 games in all competitions this season.
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