Rio Ferdinand believes signing Alexander Isak ‘will win Arsenal the Premier League,’ urging the Gunners to forget about signing Martin Zubimendi this summer.. While the Gunners still have 11 games of their league campaign remaining, their hopes of challenging Liverpool for the title are fading fast having dropped points against West Ham United and Nottingham Forest in recent weeks.. Their title bid has been undermined by key absences across their attack with Bukayo Saka ruled out since December and Kai Havertz ruled out for the rest of the campaign.. Gabriel Martinelli has been another key absentee in recent weeks.. But Arsenal’s inability maintain a title challenge this season could be traced back to their failure to sign a centre forward last summer, failing to add to their squad in the January transfer window.. Newcastle United star Isak has been among their top targets but a huge asking price at St James’ Park could place him out of reach.. But former Manchester United defender Rio Ferdinand believes the Swede is the obvious candidate to transform Arsenal from contenders to champions.. “Arsenal fans have been calling out for a No.9 for two or three years,” Ferdinand told Rio Reacts (via Metro).. “If you can sign Isak, you’ve got to do it. They could win the league with him because he’s phenomenal and gives them something different.. “They’ve put so many good pieces in but they need that little extra now.”. Arsenal do appear set to strengthen in other areas this summer with the club thought to have agreed a deal to sign Zubimendi from Real Sociedad in a £51million deal.. The 25-year-old rejected a move to Liverpool last summer with Manchester City also admirers of the midfielder, who replaced Rodri during last summer’s European Championship final to help Spain lift the trophy.. Arsenal signed Mikel Merino from the same Spanish club last summer and would appear to be well stocked in midfield, although reports suggesting Thomas Partey will leave at the end of the season could change that.