Stunned Chelsea fans found themselves sitting next to manager Jose Mourinho after the Portuguese was sent off during his side's
Mourinho was ordered from the technical area by referee Anthony Taylor after protesting about apparent time-wasting.
Chelsea assistant first-team coach Steve Holland said: "Jose was furious on the touchlines.
"For an hour, we'd been frustrated by their clear time-wasting."
Mourinho spent the final 20 minutes sitting among supporters behind the Chelsea dug-out, with one fan using Twitter to post a photograph of himself sitting next to the Blues manager.
Holland added: "Jose is very frustrated. From the first minute, they took a long time to take every dead ball.
"We mentioned it politely to the fourth official and referee. It was a deliberate ploy to break up the game.
"That changed when we got ahead. They kicked the ball out for us to take a throw in. The ball boy went to get it, threw the ball to Ivanovic, missed, and so it was in the dug-out area.
"Ivanovic had the ball in his hands for two seconds - and the referee was gesticulating for him to get it back into play.
"Jose was furious on the touchlines. For an hour, we'd been frustrated by their clear time-wasting.
"It's very frustrating for Jose to then be sent off for protesting after we have to throw the ball in within two seconds of getting it."
Mourinho was last sent off in May, when still Real Madrid manager. He protested after a decision went against his team in the Copa del Rey final defeat by city rivals Atletico.
In November 2010, he was charged with unsporting behaviour by Uefa, after allegations two Real Madrid players got themselves sent off in a Champions League match.
He was also sent off the season before, while managing Inter Milan against Juventus.