Eifion Gwynne, 41, from Aberystwyth, Ceredigion, was in Malaga for a friend's funeral when he died on 22 October 2016.
The father-of-three had played rugby for Aberystwyth and Llandovery.
Ceredigion coroner Peter Brunton recorded a conclusion of death by misadventure at a hearing on Wednesday.
He said he suffered a number of serious injuries to his upper chest.
The inquest heard Mr Gwynne had been drinking for up to seven hours after attending the funeral before getting a taxi back to his hotel.
In a statement, his friend David Thomas described him as being drunk but also "coherent and capable" when he got into the taxi.
The inquest heard he was hit by a car in the early hours of the morning on an unlit section of the A7 motorway near Estepona.
The driver told police she had been travelling at about 50mph (80km/h), in the inside lane.
Mr Brunton said: "We don't know what happened between the English speaking barman [who had arranged the taxi for Mr Gwynne] and the taxi driver.
"Whether or not there had been a misunderstanding and he'd taken him to the wrong address - that's just speculation on my part."
About 1,200 people attended Mr Gwynne's funeral and 4,000 people watched a charity rugby match which was played in his memory in May.
A rugby player died after being hit by a car on a dual carriageway in Spain, an inquest has heard.