A late penalty keeps the visitor's qualification hopes alive for the return next week as the hosts secured their seventh straight continental victory at home
The game started off slowly, with neither side able to impose their will on the game, as the first sign of danger came only in the 38th minute, when Daniel Carrico tried his luck from distance, but his shot went straight into the hands of Olexandr Goryainov.
Four minutes later, the Ukrainian goalkeeper was at fault as he failed to clear a free-kick from Matias Fernandez, and the ball fell into the path of Ricky van Wolfswinkel, who could not direct his shot goalwards.
After such a poor first half from both sides, Sporting came out strongly from the interval and broke the deadlock after just six minutes. Diego Capel and Emiliano Insua exchanged passes on the left flank before the Spanish winger squared for Marat Izmailov to slide home.
Sporting were now in the driving seat and doubled their lead in the 64th minute, when Insua sent home a low free-kick targeted at the right corner of Goryainov's goal.
Metalist came close to scoring on 74 minutes, when Cristian Villagra picked up the ball inside the Sporting box and sent in a low cross for Taison, whose shot at point-blank range was denied by Rui Patricio.
The Ukrainian side reduced the deficit in injury time as Patricio brought down Marko Devic inside the area after stopping Marlos' initial shot with a flying save. Cleiton Xavier made no mistake from the spot and sent the Portuguese keeper the wrong way.
The result leaves the tie wide open for the return leg in Ukraine on April 5. The Leoes have reasons to celebrate, however, as they have equalled Barcelona's record for the highest number of consecutive continental victories after securing their seventh Europa League success at the Estadio de Alvalade in 2011-12.