"You want to follow him. You want to fight for him. You want to die for him on the pitch. We showed that today." Kobbie Mainoo's assessment of manager Michael Carrick on Sky Sports after Manchester United beat Liverpool 3-2 in the Premier League resonated. It resonated because when Mainoo scored his 77th-minute winner at Old Trafford, the stadium announcer made a point of hailing the homegrown, local-born 21-year-old, who signed his new long-term contract on Thursday. Mainoo has become the poster boy for the club. That is amazing because he had a request to join Napoli on loan turned down last summer, did not start a league game for the first five months of the season and was preparing for tough discussions over his future in January before Ruben Amorim got the boot.…