Valencia's David Silva has told skysports.com of his contrasting emotions heading into Wednesday's game against Chelsea.
Silva was victim of elation and desperation when the two sides met in last season's UEFA Champions League quarter-finals.
In the first leg at Stamford Bridge the 21-year-old opened the scoring with a stunning strike that left the Chelsea faithful stunned.
Valencia took a 1-1 draw back with them to the Mestalla and as the second leg drew to a close the match looked destined for extra-time at 2-2 on aggregate.
But Chelsea's Michael Essien dealt Valencia a bitter blow when he netted an injury-time winner.
Silva described his feelings ahead of the clash against Avram Grant's side.
"When I speak about Chelsea, the best and worst experience of my sporting life comes to mind," he explained.
"I scored the goal at Stamford Bridge. But we were knocked out in Valencia, it was a terrible night for us."
The Spaniard also voiced his belief that The Blues are currently riddled with problems, and is more determined than ever to avenge last season's heart wrenching exit.
"Now the situation has changed and the English side arrives to the Mestalla with many problems. It is the perfect moment for us to win the match," he added.
"Chelsea is in crisis following the change on the bench and the scores, but they still have great men at their disposal who are a danger.
"Mourinho's exit was a surprise to me. The Portuguese was key in the club, and the next month is possibly difficult for the new coach.
"If we win at the Mestalla the players will have returned part of the sadness that we lived in last season's Champions League."