U.S. Davis Cup captain Jim Courier analyzes the prospects of the United States younger and mid-20s group of male players. Courier sees big things ahead for John Isner and Sam Querrey, and likes the progress that Donald Young and Ryan Harrison made last year.

"Isner had a great second half of the season," said Courier of the 18th-ranked North Carolina native. "He's basically in my view in the same spot that Mardy Fish was in this time last year. He has a great shot at the top 10 in the first half of the year. If he plays the way he's been playing, he'll get there. He's already working out physically. He's getting geared up to start bashing some balls and really get a running start into the season. Upside potential is big with John. He's probably the most disruptive force in the men's game. His serve is just a monster. No one from the top down likes to deal with it. He's not the best player in the world by any means, but he's probably the player that's least enjoyable to play. If he keeps getting better, top ten is where he should live with that serve."

Young, who reached his first career ATP final in Bangkok finished ranked No. 39 after having a strong fall. "He has a big opportunity in the first half of the season, like Isner, as far as ranking points go," Courier said. "If he can string some wins together, his ranking is only going to climb in the first half of the year until he has to defend some points. For me it's a new beginning for Donald because he's now established on the tour and now is his chance to really prove that not only is he going to be a tour player but he can move forward and maximize the potential we all know he has."

Former top 20 player Querrey was off much of the summer after undergoing elbow surgery. but has fought his way back into the top 95. "He's a guy who should be in the top 20," Courier said. "I have a lot of respect for Sam dipping down and deciding to go play some minor league tournaments to get his confidence back in his body.. He didn't stand behind a protected ranking. He said, ‘I'm good enough to get up there. I'm going to get back there in due time as long as I feel healthy. It's going to be a big year for Sam. If he stays healthy, I expect to see him back pretty quickly inside the top 50."