Gyokeres' return of 97 goals in 102 games for Sporting meant that Arsenal probably would have felt that, at worse, he would have had no trouble finding the net this season. He also boasted previous experience in England with Coventry City, ripping up the Championship and coming within a penalty shootout of promotion in his final year with the Sky Blues. There was probably some theory that as long as he was standing in the right places, the Gunners' creative and other attacking outlets would find him.
This has not been the case. Gyokeres has blanked in 18 of his 23 Arsenal appearances to date. Two of his seven goals have been penalties. Remarkably, he still is the team's joint-leading scorer both in the Premier League and in all competitions, though this is more down to the their strength in depth and proficiency from set-pieces, spreading the love right through a deep squad - 15 different players have scored, while Arsenal have benefitted from four own goals too.
Given the expectations set for Gyokeres, he ranked sixth on GOAL's list of the 11 most disappointing Premier League signings so far this season. We're not writing him off, but he hasn't given us a reason to be too impressed just yet.
Gary Lineker, one of the finest strikers England has ever produced, believes Gyokeres needs to be doing more off the ball in order to improve both his goal tally and importance to the team, telling the Swede to take a leaf out of the in-form Dominic Calvert-Lewin's book.
"I've watched him quite closely the last few weeks and I think he's like most strikers, is one that waits to see where it's going, the ball, waits until it's crossed and then attacks the space," Lineker said of Gyokeres on The Rest Is Football podcast. "That's what defenders do, as a striker you got to gamble on where you think the ball might go and you go just as they're about to cross it. You steal a march on the defender that way and lots of the time the ball won't go there, but I don't see him doing that very often.
"Dominic Calvert-Lewin did a perfect example of how to do that for the Leeds goal at Sunderland, perfect. He didn't wait and to see where it was going to go. He went, 'Right, I pulled away and then he sprinted at the near post and hoped that the ball would be delivered there and it was'. I don't see that too often from Gyokeres at present, the players that score big numbers will do that. You know, [Erling] Haaland, [Harry] Kane, [Robert] Lewandowski, they know how to make those kind of moves into those spaces. Is it something you can learn? I've always thought yes, but because it's actually common sense because it's law of probability when you think about it."