John Terry may have played his final game for Chelsea following his red card in the 3-2 defeat to Sunderland, and Guus Hiddink rued referee Mike Jones' decision.
After being booked for a foul on Defoe, Terry was shown a second yellow card in the fifth minute of second-half stoppage time when he collided late with Wahbi Khazri.
Having already seen red in the 3-0 win over West Brom last August, the FA confirmed to Omnisport the Chelsea captain will subsequently serve a two-match ban, ruling him out for the remainder of the campaign.
With no resolution over Terry's contract, which is due to expire at the end of the season, the defender - who has been at the club since 1995 - may not appear again, and Hiddink was disappointed with the dismissal.
"John Terry was a double yellow, I think it was a little bit over the top, the decision," he told BBC Sport.
Terry made his Chelsea debut in 1998 and captained the side for the first time as a 20-year-old before going on to make over 700 competitive appearances for the club.
The centre-back has been the figurehead of the most successful period in Chelsea's history, claiming four Premier League titles, five FA Cups and the Champions League in 2011-12.
"For the club I don't know [if it's his last game], but it's sad of course. I think the referee was too close to the incident and an impulsive reaction made him draw the yellow card," Hiddink added.
"Sometimes if you have a little bit more distance you can see it was a good duel between the players. Give yourself time, be experienced a bit and it was not the intention to hurt whatsoever. So for me, too harsh.
"It was an intense game and you have to consider that in this duel, so it was too harsh [of a] decision.
"We don't know what his future is at this moment, but for this season it's sad because it would have been lovely to have him in our last game at home. It's sad he's not participating in that."
