Ayew stroked home his 17th goal of the season shortly before half-time as Swansea, marshalled superbly at the back by Ben Cabango and Marc Guehi, were rarely threatened. When they were, goalkeeper Freddie Woodman made crucial saves, and Carlton Morris struck the crossbar in added time.
Steve Cooper’s Swans, who were beaten at this stage of the play-offs last season, will look to hold onto their slender lead when the teams meet again at the Liberty Stadium on Sunday, while Barnsley are up against it having failed to make the most of the return of supporters to Oakwell for the first time in over 14 months.
Story of the match
The return of a limited number of fans gave Oakwell a colour and life absent for far too long, but they saw little goalmouth action for much of the first half. Barnsley’s intense style was effectively squeezing any Swansea threat, but the visiting defence was up to the physical threat posed and battled to nullify it.
The main risk for Barnsley was their high defensive line, and they were finally caught out six minutes before the break. Kyle Naughton’s pass released Ayew, who calmly came inside Michal Helik and stroked into the far corner.
Only after that goal did the hosts muster a real effort on target, but Guehi did enough to make life difficult for Helik and the Pole could only head tamely towards Woodman from Romal Palmer’s cross as they went into the break behind.
The match, and especially Barnsley, only really came to life after that interval, aided by the introduction of Morris from the bench. He sparked the first flurry of chances with a run and strike which was only parried by Woodman, who quickly made up for it with a brilliant recover to deny Callum Brittain’s rebound effort.
Skipper Alex Mowatt had a volley deflected off target, with Daryl Dike subsequently heading Cauley Woodrow’s corner wide. Further waves followed and Woodman was called upon again to keep out a Woodrow free-kick, before Morris sliced a volley over.
Once Swansea managed to weather that storm, they looked comfortable once more and were rarely troubled for the rest of the second half. There were fleeting chances for them to double the lead, with Jamal Lowe flashing over after fashioning a good chance and Ayew denied another by Mads Andersen,
They had to survive one nervous moment in added time when Morris flicked a corner onto the frame of the goal, but they held on to take the hard-earned one-goal advantage back to South Wales.
Man of the match - Marc Guehi (Swansea)
Swansea showed their ability to fight against Barnsley’s now-notorious style and their defence stood up brilliantly, especially Chelsea loanee Guehi.