Asoro joined the Swans last summer but has failed to impress at the Liberty Stadium.
The 20-year-old attacker made the move to South Wales last summer, joining from Sunderland on a four-year deal for an undisclosed fee which Wales Online claims to have been in the region of £2million.
Former Swans boss Graham Potter was said to be a long-time admirer of Asoro from his time at Ostersunds FK, making the Sweden Under-21s ace his first signing at the club (BBC Sport), but the player struggled to make an impact at the Championship side.
Asoro made a total of 17 appearances in all competitions for the first team last season, four of which were starts, and failed to get on the scoresheet, while this term, under Steve Cooper, he was not included in the matchday squads for the games against Hull City, Derby County and Northampton Town.
According to BBC Sport, Groningen have the option to sign Asoro on a permanent deal next summer as part of the loan agreement, which suggests that the Swede's time at the Liberty Stadium is probably coming to an end.
Here is what some Swansea fans said on social media about the announcement:
Good luck Joel bags of talent go show it out in Holland— dave (@GucciGovea) August 15, 2019
You’ll be returning to a Premier League side. Go smash it #YJB— Tom (@ThomasChudleigh) August 15, 2019
Good move know you’ll smash it— cameron was (@petersonsprime) (@AmbitiousAyew) August 15, 2019
What a flop!— bryn. (@Brynmac10) August 15, 2019
Who???— Paul johnson (@enfysjack) August 15, 2019
Good Luck !— Brazil Swans (@BrSwansea) August 15, 2019
What a flop— Joe (@jwinteerrr) August 15, 2019
Not matter what age a player is 17 or 37 the quality and footballing abillity is always there you never lose that. From what asoro is shown the footballing abillity just isn't there— YanksOut (@ill_shank_urDad) August 15, 2019
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