Antonio Conte believes Chelsea have passed a psychological test after bouncing back from a recent bout of indifferent form by reaching the FA Cup final and taking another significant step towards the Premier League title in the space of four days.

Chelsea need four wins from their final five matches to be sure of becoming champions after holding their nerve to beat Southampton 4-2 and move seven points clear of Tottenham Hotspur, who will be under pressure when they visit Crystal Palace on Wednesday. The leaders have responded impressively to their setback at Manchester United 10 days ago.

Chelsea tighten title grip after Diego Costa scores twice against Southampton Read more

“I think that we passed a big, big step,” Conte said. “A big psychological step after the defeat against United. Because, against United, we lost three points and then you had to prepare 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 psychological test, and our answer was very good. For this reason I must be pleased.”

Tottenham can still reduce the gap to four points if they win at Selhurst Park, however, and Conte urged his players not to become complacent about the threat posed by Mauricio Pochettino’s side. “We must think this race is open,” Chelsea’s manager added. “We reached the final of the FA Cup but the other situation in the league is totally open. But we are ready to fight until the end.”

Conte added that speculation about Diego Costa’s future was being caused by troublemakers after the striker, linked with a summer move to China, scored for the first time in five league matches. “I continue to repeat this concept: it’s important to be focused on the moment because the moment is very important for all of us,” the Italian said. “In this period, I’m reading a lot of speculation about every one of us. It’s right to be focused. I’m sure my players are focused on our targets.

“It’s normal at this part of the season to have someone who wants to put problems in your team, to create also ‘not order’, but we must be stronger than this speculation. We must be compact and think our target is really [more] important than the other teams’.”

It was not all plain sailing for Chelsea against Claude Puel’s enterprising side. They were looking edgy after Oriol Romeu had cancelled out Eden Hazard’s early goal midway through the first half, but Gary Cahill restored their lead just before half-time and Costa made the game safe with a fine double in the second half.

Conte praised the Spanish international’s attitude and workrate. “It’s normal for the strikers, for the forwards, that it is important to score,” he said. “The goals are their life. But, for me, I’ve always said I’ve been pleased with his commitment, his work for the team. He always worked for the team.

“Sometimes he was unlucky in different circumstances, but I was always confident about him. After the Tottenham game I said I’m sure he’s keeping his goals for the final weeks of the season. Now he must continue. He’s very important for us. His confidence is very important for us.

“He scored two very beautiful goals, good combination and technique between him and his team-mates.”