The defender earned his fourth international cap as Iceland played out a 0-0 stalemate against Romania in Bucharest.
Gretarsson is yet to make a league appearance for Blackpool this season, with his only cameo coming in the Carabao Cup loss against Sunderland in August.
The 26-year-old – who joined the Seasiders a year ago – has so far struggled to even get in Neil Critchley’s matchday squad and has made more appearances for his country than he has for his club this season (3).
Iceland are now unable to qualify for next year’s World Cup after winning only two of their nine group games.
Here are the best of today’s rumours...
7. Everton starlet wanted by Blackpool
Blackpool want to resign Everton's Ellis Sims after his successful loan spell at Bloomfield Road last season. The forward scored ten goals for the Seasiders. (Liverpool Echo) Photo: Nathan Stirk
8. Millwall open to permanent deal for striker
Millwall are open to signing Stoke City loanee Benik Afobe on a permanent deal with his contract at the bet365 Stadium expiring next summer. The 28-year-old has scored three goals this season. (The 72) Photo: Jacques Feeney