I so badly want to be a jack sock fan but losses like this make it hard. He clearly has the equipment as evidenced by his success at majors. ( relative success). But he doesn't seem to have the mental strength or discipline to do it week in and week out. As shame
Patience, young Padawan!
The days of younger players having success on the tour are over. There isn't even one teenager in the top 150.
But yes, Jack Sock will have to improve a lot in those areas if he wants to make it.