PHOENIX -- A Glendale man was sentenced to 28 years in prison Friday for the 2007 beating death of an Air Force veteran.

Maricopa County prosecutors said Andrew Robins, 30, pleaded guilty to second-degree murder and burglary in September.

Authorities said Roger Staats, 65, of Peoria, was riding a bicycle in Glendale on Jan. 28, 2007, when he tried to intercede in a roadside argument between Robins and Robins' girlfriend.

Investigators said Staats pedaled toward the parked car and asked Robins' girlfriend if she needed any help. They say Robins pushed Staats from his bicycle, then hit and stomped on him repeatedly around the head.

Staats was taken to a Phoenix hospital, where he later died. Robins fled and broke into a construction yard where he tried to steal a forklift before being arrested by Glendale police.

The slaying occurred about five weeks after the victim's 30-year-old son -- Army Staff Sgt. David Staats -- was killed in a roadside bomb attack in Baghdad.