Asked if he had been thinking about Pete Sampras's modern-era record at the grasscourt grand slam, Federer said: "Well, maybe, obviously a little bit because I'm aware of the great things he achieved, being one title away from it.
"But then again, you have to break it down and make it simple for yourself, trying to win the first round, being here, trying to defend the title before everything."
The Swiss top seed plays Falla for the third time in consecutive tournaments, having beaten him at the French Open and Halle.
Last year's beaten Wimbledon finalist, Andy Roddick, is second on No1 Court against fellow American Rajeev Ram.
Following that match, five-times champion Venus Williams, playing in her 50th grand slam, takes on Paraguay's Rossana De Los Rios.Paes-Dlouhy in QFs of UNICEF Open
Venus Williams beats Peer to reach Dubai final
Roger Federer: 700 and counting...
Hewitt stuns Federer in Halle final
Bopanna-Qureshi advance to UNICEF Open quarters