Antonio Conte praised the mental resolve of his Chelsea side after they re-established a seven-point Premier League lead over Tottenham.
Diego Costa ended a seven-match scoreless streak with a double as the Blues beat Southampton 4-2 on Tuesday night, putting the focus back on nearest rivals Spurs, who play at Crystal Palace on Wednesday.
Chelsea responded from the loss at Manchester United, which saw their advantage at the Premier League summit cut to four points, by beating Tottenham to advance to the FA Cup final and then defeating Saints.
Blues head coach Conte said: “We passed a big step, a big psychological step after the defeat against United.
“Against United we lost three points and then we had to prepare for a semi-final against Tottenham and then another tough game in the league.
“I think that in that moment we have had a really important test, psychological test. Our answer was very good. For this reason I must be pleased.
“But we must think that this race is open. We are ready to fight until the end.”
Chelsea’s prospects of a trophy double in Conte’s first season in charge remain alive, with 12 points needed from the final five games to clinch the league title before the May 27 FA Cup final with Arsenal.
“Everyone feels a bit of pressure,” Conte added.
Costa ended a seven-match scoreless streak for Chelsea with goals at either end of the second half, taking his tally to 51 in 85 Premier League games.
Conte said: “For strikers it’s very important to score. Goals are your life.
“I always said I’m very pleased with his commitment, his work for the team. I was always confident about him.
“Now he must continue.”
Eden Hazard and Gary Cahill scored in the first half for Chelsea, while former Blues duo Oriol Romeu and Ryan Bertrand replied for Saints as Conte’s men conceded for an 11th successive Premier League game.
Conte’s frustration with his side’s defending was evident when he kicked a medical bag in his technical area during the second half.
He said: “In that moment I wanted to kick the ball and I took the bag as a ball, because sometimes I want to play.”
John Terry came off the substitutes’ bench for his 714th Chelsea appearance and first in the league since November.
Terry, who has won 14 major trophies at Chelsea, will finish his Stamford Bridge career this summer and may do so lifting more silverware.
Southampton boss Claude Puel rued the concession of goals at crucial periods in the game.
“It’s a shame that with the quality of this game we conceded four goals,” Puel said.
“We conceded the goals in bad moments, after five minutes, just before half-time, just after half-time… this made the difference.”