Cesar Azpilicueta was furious after Chelsea's defeat by Arsenal and was seen confronting some fans inside Stamford Bridge.
The Blues suffered a damaging defeat to their city rivals as Eddie Nketiah's brace secured a 4-2 victory for the Gunners.
Chelsea were second best throughout the majority of the game and tempers flared at full-time as skipper Azpilicueta approached a fan and appeared to be pleading with him to support the team rather than complain as groans rang out around Stamford Bridge at full time.
Thomas Tuchel saw the incident and admitted he understands where the fan's frustration comes from. He said: "I saw it. Honestly, I can understand the fan."
Azpilicueta was in the thick of the action throughout the 90 minutes scoring the goal that got Chelsea back on level terms at 2-2, before hauling down Bukayo Saka in the box as the England winger wrapped up the three points from the penalty spot.
The Spaniard complained to the referee about the decision and was raging that Saka went down, but the foul was as clear as day. And Saka was dumbfounded by the defender's angry reaction.
He said: "Of course, he is going to be angry with me but it is what it is. It was a penalty. He was holding me for five seconds. I had to go down."
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Saka was delighted with Arsenal's spirit bouncing back from three defeats on the bounce. He added: "We wanted to give the fans something to believe in us and I think we've done that today. We showed fight, character and it's a huge result for us. It means a lot to us. Losing three games in a row is really difficult."
Tuchel bizarrely blamed the Stamford Bridge pitch for his team’s defeat and rued Andreas Christensen’s mistake for Nketiah's opening goal.
The German said: “To say the pitch is difficult to play here, it sounds maybe like an excuse but it is a very difficult pitch we have here. It is not to our favour and the ball bounces very, very awkwardly when the ball bounces to Andreas.
“Totally wild and open game in the first half. Already a 2-2, came back twice, we had a good start, gave again a first goal again which is absolutely impossible to do these things in consecutive matches. We are doing it.”