Guus Hiddink thanked Chelsea fans for their support during the 2-2 Premier League draw against Watford at Stamford Bridge on Boxing Day.

Cesc Fabregas and Diego Costa were booed before kick-off and when substituted in the victory over Sunderland last weekend, while Jose Mourinho's name was sung throughout in the first game after the Portuguese's departure.

Against Watford, Costa received a far better reception after scoring his second of the match to bring Chelsea level against Quique Sanchez Flores's side.

Hiddink — in the Stamford Bridge dugout for the first time since retaking the helm — admitted the supporters were within their rights to voice their discontent last weekend but wants the club to move forward with unity.

"I think this crowd is very loyal and also we must not deny what has happened recently," he said. "They had the right to express themselves in the previous period, but we have to go forward and the crowd was supporting us well.

"What has happened in the recent past, they [the players] have to learn a lesson and show ambition to go forward."

The Dutchman was pleased with the resilience shown as his team came from behind, but rued a missed penalty from Oscar with 10 minutes remaining.

"It was an intense game, but I enjoy it more when we win and we had a possibility to win," Hiddink said. "Unfortunately, Oscar slipped away on the penalty, but what I liked very much was the reaction after two unfortunately conceded goals. The team reacted at 2-1 down, they reacted well."

Hiddink also lamented Costa's suspension for Chelsea's Premier League meeting with Manchester United on Tuesday (AEDT).

"He is out, which means that we have to think how to solve that problem," Hiddink said.

"It is a pity after a good performance, we have to solve that in 48 hours."

Hiddink praised Costa's response to the criticism he received last week, but denied he, as manager, was responsible for the upturn in form.

"Don't overestimate the influence of managers. You try to give people focus," Hiddink continued.

"When he was booed when he was substituted [against Sunderland] his reaction was very good.

"It was a very professional reaction as it made him think: 'How should I go on?'

"He focused on what he is good at and he's very dangerous, that's important, not wasting energy where he shouldn't waste it.

"Everyone knows what he is capable of … he showed that today with two terrific goals."

Goalkeeper Thibaut Courtois also praised the character shown by his team-mates and felt the Stamford Bridge faithful were behind them.

"Everybody was running and fighting and that is a good spirit. I think our game was good, we just had bad luck with those two goals," he said. "The fans, I think, were behind us and that is good because we need the support.

"Whatever happens we have to stick by the team and by the club. Now we have to go with confidence to Manchester United [on Monday]."