Generation defining centre-half partnerships tend to only come around, well, once in a generation or so. From Steve Bruce and Gary Pallister of the 1990s to the double-winning glory days of Rio Ferdinand and Nemanja Vidic, with Camp Nou heroes Jaap Stam and Ronny Johnsen in between. Now, it may feel like asking for trouble suggesting that Leny Yoro and Lisandro Martinez can become the modern day answer to Bruce and Pallister, or Ferdinand and Vidic. Talk about setting the bar high. 18-year-old Yoro has not even played a competitive game for Manchester United, after all. Martinez, meanwhile, sp…