As far as the way the Sox utilize their speed, Nava has no speed to utilize. He is slow as molasses. Should not have been brought in tonight.
That said, the Sox do a poor job of using the speed they have. While you cannot completely discern instinctive base running plays by the player from calls from the dugout, it almost looks like the Sox players with the exception of Nava, make better instinctive plays on the base paths than the Sox coaches make via called plays. That is sort of remarkable.
But Nava's problems on the base paths are not known by now by all of us. Farrell should know it by now as well. I just don't know what to say about that. While we are all rank amateurs here compared to MLB coaches, I don't think a single one of us would have looked down the Red Sox bench tonight and pointed to Nava to go in to run for Lavs with other options sitting on the same bench and the game on the line.