Graham Potter admitted he was surprised by some of the criticism levelled at Viktor Gyokeres this season, insisting he remains a vital part of Sweden's World Cup push.

Gyokeres scored the goal that sent Sweden into this summer's tournament, netting an 88th-minute winner in their 3-2 victory over Poland in March's UEFA play-offs.

He has scored 20 goals for Sweden in all competitions, including a free-kick in their 2-2 friendly draw with Greece on Thursday.

Gyokeres made the move to Arsenal last summer after leaving Sporting CP, where he enjoyed a hugely prolific two seasons, netting 97 goals in 102 appearances across all competitions.

The forward helped end the Gunners' 22-year wait for a Premier League title and reach the Champions League final, finishing as their top scorer in all competitions with 21 goals.

However, his record was still questioned, with Potter highlighting Gyokeres' importance for both club and country.

"He scored four goals in two games, got us to the World Cup, so his impact is incredible," Potter said.

"From Arsenal's perspective, he's played his role, scored his goals, and the team have won the Premier League and got to the Champions League final.

"He has played most of the games, but he still gets criticism. That's just the world we're in, but then you look at him, how much work he does, how he goes about his business, and he's an incredible character."

As well as Gyokeres, Potter also has Alexander Isak to call on, with the Liverpool striker having a disjointed first season on Merseyside following his British record transfer from Newcastle United last summer.

Isak finished the campaign with just four goals, having been sidelined by a fractured leg, but Potter expects him to go on to do big things with Liverpool.

"I think it's fair to say it probably hasn't gone as well as he would have liked – and anybody would have liked – but sometimes these things happen," he explained.

"We sometimes assume that when you sign a player, it's automatically going to improve everything. We know what Alex did for Newcastle, but how does he adapt to what Liverpool want him to do? The player doesn't change. His quality doesn't change. It's just how they interact as a team.

"The injuries have been disappointing for him, but he's a great, great lad, he wants to play and wants to help his team.

"Your career can go up and down, but the quality of the person and the quality of the player is undeniable from our perspective."