Chelsea boss Maurizio Sarri said he was pleased with how his side "suffered" before beating Slavia Prague in their Europa League quarter-final first leg.
Marcos Alonso's late goal secured a 1-0 win from a difficult match in Prague.
Sarri said his side have improved from earlier in the season when they would "immediately concede" in difficult moments.
"In the past, we were not able to suffer in the difficult moments of a match," said the Italian.
"Now we are able to stay in trouble and suffer without conceding."
An under-strength Chelsea struggled to find any rhythm for large spells but grew into the game after Eden Hazard was introduced off the bench just before the hour mark.
Alonso timed his run perfectly to meet Willian's right-wing cross with a firm header four minutes from time at the Eden Arena.
Arsenal's Europa League quarter-final tie with Napoli is "still 50-50" according to Gunners boss Unai Emery, despite his side winning the first leg 2-0 at Emirates Stadium.
Aaron Ramsey converted Ainsley Maitland-Niles' pass to finish off a good team move and give the hosts the lead.
Kalidou Koulibaly then scored an own goal when he deflected Lucas Torreira's shot past goalkeeper Alex Meret.
The impressive Meret stopped the Gunners winning by more.
Napoli, who are second in Serie A, host the Gunners in the second leg next Thursday at the San Paolo Stadium (20:00 BST).
"The first leg was very important to take a good result," said Emery. "We deserved to win, but we know it is going to be very difficult there.
"Their performances at home are usually very strong. We will plan to win the match, but we need to have a lot of respect for them. It is still 50-50. Our challenge is to be competitive away. Sometimes away we lose the spirit we have at home."
Napoli boss Carlo Ancelotti said he is still "confident" of progressing to the last four.
"The result is difficult to change but we have 90 minutes left," the Italian said.
Portuguese 'eagles' beat German 'eagles' with 4 goals. Overall, 6 goals were scored in Benfica-Frankfurt match. (4-2)
Valencia became the winner of the match with 2 last-minute goals. The 1-3 score made a winner of Valencia over Villareal in away match.
