Anthony Aragon saw the bicyclist on his right and prepared to carefully pass him.
But the off-duty Border Patrol agent said the bicyclist veered into his lane, causing him to strike 47-year-old Floyd Hancock in New Mexico on Saturday morning, the El Paso Times reports.
Aragon jumped out of his car and performed CPR on Hancock, New Mexico State Police spokesman Sgt. Emmanuel Gutierrez told the Times.
Hancock was taken to a hospital and pronounced dead.
The accident remains under investigation.