The Costa Rica international joined the Gunners in 2011 but spent the following three seasons out on loan in Europe, playing valuable first-team football while gaining a work permit.
Following his World Cup exploits in Brazil, many supporters in North London called for his return and subsequent inclusion in the first-team squad this season.
While boss Arsene Wenger duly obliged, the former Saprissa man soon found Premier League opportunities hard to come by due to the heavy competition for attacking places in North London.
Campbell was sent out on fourth loan, joining Villarreal in the January transfer window, but without particularly impressing there are doubts as to whether he has a long-term future at the Emirates Stadium.
The Turn-based outfit currently lie in seventh spot in the Italian top flight, but with just 34 goals scored in 29 matches it’s fairly obvious where they need to strengthen this summer.
Campbell has failed to score in 15 matches in all competitions in Villarreal, but having regularly been played out of position on the wing in an orthodox 4-4-2 formation, that isn’t particularly shocking news.
The 22-year-old’s contract with the Gunners is to expire in the summer of 2016, meaning Torino could perhaps strike a bargain with the North Londoners and finally give the striker a permanent home.