Rangers, if things work out as planned, could have a handy £2.5 million windfall heading their way this summer. The Glasgow giants need no introduction to the benefits of loan-to-buy deals. Ianis Hagi and Ryan Kent joined the Scottish Premiership giants on a permanent basis after impressing during initial rental periods. Oscar Cortes could do the same, providing the Lens-owned winger recovers in time and picks up where he left off before that ill-timed injury. Rangers have an option-to-buy clause in Cortes’ contract. Mohamed Diomande, another January signing, was brought in on a short-term bas…