Barcelona dominated from that moment, with Lionel Messi assisting all three of Tello's strikes, which have handed the Catalan outfit a comprehensive lead ahead of the second leg.
Here, Sports Mole dissects the 90 minutes of action between the two La Liga rivals.
On target: 2
On target: 8
Was the result fair?
There is no question that Levante were the better side in the first period and they deserved to take a one-goal lead into the interval. However, they simply failed to show in the second. The home team struggled to match Barcelona's intensity as the fixture gathered pace and the Spanish champions utterly dominated proceedings for long spells. A 4-1 scoreline is perhaps slightly harsh, but the visitors were stunning in the second 45 minutes.
Levante would have been buoyed by their 1-1 draw with Barcelona in the league at the weekend, but both managers made a number of changes this evening. They matched the away side all over the park in a pulsating first period, but Barcelona took control when Levante's work-rate dropped. The equaliser was a real blow to their chances, while they simply granted Messi too much space in the latter stages. Levante need a monumental collapse from Barcelona next week if they are to turn this quarter-final around.
There were perhaps some stern words exchanged at the interval due to Barcelona's lacklustre display in the first period. Gerardo Martino's side were second to every ball in the opening half, but that was simply not the case in the second 45 minutes. As Levante's intensity dropped, more space opened for the likes of Messi and Tello to exploit. There were a couple of nervy moments defensively, especially in the first period, but they utterly coasted for long spells.
Sports Mole's man of the match
Cristian Tello: It hasn't quite happened for Tello this season, but he was magnificent in Valencia. Levante simply could not deal with the winger's movement and pace, while he demonstrated his finishing ability with a second-half hat-trick, which was his first for Barcelona. That said, a loan move from the Camp Nou could still happen in the latter stages of the transfer window. He will likely not be short of offers.
Loukas Vyntra was the hero at the weekend with his goal securing Levante a point against Barcelona in the league, but the Greek had a horror moment in the second half this evening. With the ball bouncing around inside his own box, the centre-back attempted to clear his lines, only to smash the ball into fellow defender Juanfran, who could do nothing as it nestled in the bottom corner. From that moment, Barcelona took control.
It was a busy first period for Alejandro Hernandez as the challenges flew in from both sides, but the Spanish official was on hand to calm proceedings on each occasion. Meanwhile, he awarded just the three yellow cards. In truth, Hernandez was hardly seen for long spells, which is always a good sign for a referee.
Levante: Levante return to league action with a difficult trip to Sevilla on Saturday evening.
Barcelona: The La Liga leaders also return to their league duties this weekend with a home match against Malaga.