"Fields the best heavy cavalry in the west"

Yeah right. I'm just getting back into Medieval II with a French campaign and a unit of my Lancers with 3 experience and upgraded weapons just lost a 1v1 against a unit of Jinetes. I know they're lancers and aren't necessarily built for prolonged melee, but really? They didn't even get a good javelin volley off before we connected. I'm genuinely wondering if something is wrong with my game here because regardless of if Lancers are only optimally used to cycle-charge, they should be able to win that fight. Is the lack of a shield really that bad? It's not like that's too much of an issue with infantry in head-on melee, assuming equal defense stat totals otherwise. They look badass and their charges are devastating, but I don't want to have to babysit them for entire battles since they can't stand and fight for more than a few seconds. Am I doing something wrong or is the balance off? Normal battle difficulty btw.