So here it is, the draw for David's first tournament since August, last year.
He has been drawn into the bottom, i.e. Almagro's half, which looks like this:
 Pablo Andujar (ESP) vs Santiago Giraldo (COL)
Paolo Lorenzi (ITA) vs Albert Montañes (ESP)
[WC] Tommy Robredo (ESP) vs Simone Bolelli (ITA)
BYE vs  Juan Monaco (ARG)
 Fabio Fognini (ITA) vs Guido Pella (ARG)
David Nalbandian (ARG) vs [Q] Jorge Aguilar (CHI)
Horacio Zeballos (ARG) vs [Q] Paul Capdeville (CHI)
BYE vs  Nicolas Almagro (ESP)
The complete singles draw you'll find here.
In doubles, David and Rafa are in the bottom half of the draw, as well:
Nadal (ESP) & Nalbandian (ARG) vs Andujar (ESP) & Garcia-Lopez (ESP)
Marach (AUT) & Zeballos (ARG) vs  Dlouhy (CZE) & Sa (BRA)
Cabal (COL) & Giraldo (COL) vs [WC] Clezar (BRA) & Elias (POR)
Ramirez-Hidalgo (ESP) & Robredo (ESP) vs  Peya (AUT) & Soares (BRA)
Complete doubles draw here.
According to the tournament site, David's and Rafa's first-round match will take place on Tuesday, at around 8.30pm local time.