The Madrid side take 4-2 advantage to the Mestalla for second leg while late Sporting comeback sees them beat Bilbao 2-1.
Diego Simeone hails Atletico's dominant display against Valencia
Diego Simeone, the Atletico Madrid manager, described his side's performance as the best since he arrived at the club after they beat Valencia 4-2 in the first leg of their Europa League semi-final last night.
Radamel Falcao opened the scoring for the hosts early on before Jonas equalised for the visitors on the stroke of half-time.
A second-half blitz from Atleti seemed to have all but sealed their place in the final as goals from Miranda, Adrian Lopez and Falcao again put them in control, but Valencia were given a lifeline in stoppage time as Ricardo Costa headed home unmarked inside the area for a crucial second away goal.
Simeone, who replaced Gregorio Manzano in December, said: "In terms of the intensity and the consistency of the performance, this has been the best match since I arrived.
"There has been a great understanding of the type of game we wanted to play. The team understood the moment and the match."
However the Argentine coach is aware that conceding the second goal late on could still come back to haunt his side.
"The result is good, because they have been coached by a great manager for four years," he said.
"They are very competitive and we have been superior. We would have signed for this result before the game but the second goal means that we can't go to Valencia relaxed."
Unai Emery, the Valencia manager, accepted Simeone's assertion that Atleti had been the better side and said his players will need to improve in all aspects of their game to try and turn the tie around at the Mestalla next Thursday.
He said: "We were inferior, the result is just but we have two goals in our favour and the tie is open. Now they are the favourites, but we have hope in the return.
"There has to be a change in our play and mentality. We were inferior in attack, defence and intensity. In the second leg we need to return to the Valencia we have seen in patches this season.
"We have to hope that we will be different at home and I have this faith."
In the other semi-final first leg, goals by Emiliano Insua and Diego Capel allowed Sporting to produce a stirring late comeback as they snatched a 2-1 home win over Athletic Bilbao. "We turned around the result against a big team with a great performance as we were unlucky to concede the first goal," the Portuguese team's coach, Ricardo Sa Pinto, said in a television interview.