Alex Bogomolov Jr. continued a wretched start to 2012 by crashing out of the Miami Masters in an energy-sapping defeat to Gilles Muller of Luxembourg in the first round.
Bogomolov succumbed 75, 4-6, 6(5)-7 to Muller, ranked 24 places below the Russian at No. 63, in two and a half hours.
The first-round exit continues a poor start to 2012 for Bogomolov, who is competing under the Russian flag since switching from the United States last season.
Since reaching the Sydney Open quarterfinals in January, the 28-year-old has just four wins and nine defeats on the tour and in Davis Cup play.
Elsewhere at the Sony Ericsson Open, Russia's Igor Kunitsyn defeated U.S. wildcard Jesse Levine in straight, if close-fought sets 7-6 (8), 7-6(3).
In women's second-round play, Australian Open quarterfinalist Ekaterina Makarova strolled past fellow Russian Anastasia Pavlyuchenkova 6-1, 6-2, while there was defeat for Svetlana Kuznetsova, who fell 6-1, 6(7)-7, 6(7)-7 to Iveta Benesova of the Czech Republic.
Earlier, Maria Sharapova came back from a set down to beat Israel's Shahar Peer 4-6, 6-3, 6-3 and Valeria Savinykh was trounced 6-4, 6-0 by world No. 5 Sam Stosur.
