Hikaru Nakamura plays a six game classical followed by a four game rapid match in Saint Louis against Ruslan Ponomariov. The idea is to start to get some match experience. Alongside Ben Finegold plays Ray Robson (who replaced Viktor Korchnoi who developed some mild health problems after a tournament in Spain and can't travel).

http://www.chess.co.uk/twic/chessnews/events/nakamura-against-ponomariov-match-2011

Ponomariov draws first blood in Saint Louis
18.05.2011 – From May 17-25 there is an interesting match taking place at the Chess Club and Scholastic Center of Saint Louis: top US GM Hikaru Nakamura plays former FIDE world champion Ruslan Ponomariov in six regular and four rapid games. The event has unprecedented live and archived video coverage – hours and hours of it. In their first game Ponomariov was forced to mate with bishop and knight.
http://www.chessbase.com/newsdetail.asp?newsid=7227