Arsenal are stepping up their pursuit of Sporting Lisbon striker Viktor Gyökeres as they aim to reinforce their attack ahead of next season. The Gunners are preparing a lucrative contract offer for the prolific Swede, though an official bid is yet to be made. With a new centre-forward topping Mikel Arteta’s summer wishlist, Gyökeres has emerged as a prime target following a sensational goalscoring run in Portugal.