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...
1. Barcelona and Borussia Dortmund tracking Blades striker
Barcelona and Borussia Dortmund are reportedly monitoring Sheffield United striker Daniel Jebbison, who is currently on loan at Burton Albion. The 18-year-old has scored three goals in 11 appearances for the Brewers. (The 72) Photo: Christian Kaspar-Bartke
2. Stoke City could green light attacker's departure
Stoke City could be ready to allow Abdallah Sima to return to his parent club Brighton & Hove Albion in the January window amid the Seagulls' injury crisis. The 20-year-old has made only two Championship appearances for the Potters this season. (The 72) Photo: Graham Chadwick
3. Ex-Preston target dropped by Swansea City boss
Former Preston North End target Michael Obafemi has been dropped from Swansea City's squad due to 'lack of professionalism'. The Lilywhites had a bid accepted by Southampton for the forward, however he rejected it in favour of joining the Swans. (Wales Online) Photo: Tony Marshall
4. Sheffield United to push for Barcelona man in January
Sheffield United remain keen on Barcelona's Alex Collado and will push to sign the Spaniard in the January window. Slavisa Jokanovic was hopeful of a deal in summer but it broke down. (Football League World) Photo: Eric Alonso
5. Championship trio eyeing Hearts defender
Blackburn Rovers, Middlesbrough and Stoke City have all expressed interest in Hearts defender John Souttar. The 25-year-old's contract expires in the summer. (The 72) Photo: Ian MacNicol
6. Ex-Middlesbrough winger linked with La Liga move
Wolverhampton Wanderers winger Adama Traore has been linked with a move to Valencia, with the La Liga club preparing to make an offer. The Spaniard spent two years with Middlesbrough and scored five goals. (BirminghamLive) Photo: Paul Harding