Jack Sock, who many thought was the biggest hope for American men's tennis going forward, has had an abysmal year in 2018. His loss Tuesday at the French Open put his singles record to 5-11, and it all seems to be going wrong for the 25 year old who stormed into the top 10 at the tail end of 2017.

What has gone wrong? A few things, as host Joey Hanf explains.