straight to your inbox every day for freeAlan Shearer has urged Manchester United stars Marcus Rashford and Mason Greenwood to learn from teammate Edinson Cavani after the Uruguayan's match-winning exploits against Southampton.Cavani came off the bench at half-time with United trailing Saints 2-0 in Sunday's Premier League clash at St Mary's. The 33-year-old summer signing made a remarkable impact as he inspired a stunning fightback.