Williams, former Texas A&M standout Austin Krajicek and 19-year-old Denis Kudla will serve as practice partners as the American squad faces France on the clay courts of Monaco in the World Group quarterfinals April 6-8.
The four-man U.S. team is similar to the one that defeated Switzerland on the road in the first round of Davis Cup: world No. 8 Mardy Fish, No. 10 John Isner and the top-ranked doubles team of Bob and Mike Bryan. Ryan Harrison had played the tie against the Swiss because Bob Bryan was awaiting the birth of his daughter.
The French team includes No. 6 Jo-Wilfried Tsonga, No. 14 Gael Monfils, No. 33 Julien Benneteau and No. 5 Michael Llodra.
Williams has already put together an impressive start to 2012. He became the first Vol since Chris Woodruff in 2001 to reach the main draw of an ATP Masters 1000 event when he qualified for the BNP Paribas Open earlier this month in Indian Wells, Calif. He is currently ranked No. 368, a career best.
Hubble Rolls on in Doubles: Still on the road to regain his top-150 doubles ranking, former Vol Adam Hubble has been making strides toward that goal the last two weeks on the Australian Futures circuit.
Hubble and Adam Feeney won the tournament last week at the Ipswich Futures and are already in the semifinals of the Bundaberg International, a $15,000 Futures event. They beat John Millman and Ben Wagland 6-2, 5-7, [10-6] in Wednesday's quarterfinals.