Both defences were on top in the opening 20 minutes, with neither eager to concede early chances - unsurprising given each outfit had failed to keep clean sheets in their previous two LaLiga matches.
However, the game gradually warmed up and Athletic were first to threaten through Yuri Berchiche, who dribbled into the Leganes area and fired a cross-cum-shot across the goal mouth.
Almost immediately, Los Pepineros raced down the opposing end and went close to ending their three-match goal drought.
Miguel de la Fuente broke free from the Athletic defence and forced Julen Agirrezabala into a full-stretch save, with the goalkeeper showing impressive reflexes to jump to his feet and repel Sebastien Haller’s follow-up attempt.
A cagey end to the first period ensued as Alvaro Djalo’s speculative dipping shot was watched all the way by an eagle-eyed Juan Soriano to keep the scores level at the break.
Leganes came out in the second half with greater attacking intensity and were almost gifted the opener when Dani Vivian’s mistimed clearance from de la Fuente’s cross hit the post.
That opportunity sparked the contest into life, and Vivian again struck the goal frame as the defender’s overhead kick looped over Soriano and clipped the Leganés crossbar.
The towering centre-back took centre stage once more moments later, reacting to a loose ball inside the Leganes area and sending a deflected volley into the net for his first LaLiga goal in over two years.
Just as the visitors’ celebrations began to cool, Haller thought he had equalised with a powerful header, but it was ruled out for offside.
Before long, Athletic had wrapped up the points courtesy of substitute Inaki Williams, who tucked in a second from Andoni Gorosabel’s low cross.
After losing four away games in a row before defeating Las Palmas last weekend, Athletic appear to be turning the tide on their travels with consecutive victories and five goals scored - results which move Ernesto Valverde’s team into LaLiga’s top five.
Despite a three-match unbeaten run to start their first campaign back in Spain’s top flight, successive defeats have humbled Leganes, while their worrying goalless run will now have manager Borja Jimenez scratching his head for a quick solution.
Flashscore Man of the Match: Dani Vivian (Athletic Club)
