BRENTWOOD -- One man suffered major internal injuries after his cousin's car collided with another vehicle just after sunrise Tuesday, the California Highway Patrol said.

Around 6:40 a.m., 30-year-old Jimmy Leiva of Pittsburg was driving his Honda Civic eastbound on Highway 4 at Marsh Creek Road when he came to a stop light where he intended to turn left.

At the same time, 25-year-old Manuel Morales of Lathrop was traveling westbound on Highway 4 in his Acura Legend with his cousin, 20-year-old Oscar Morales in the passenger's seat, CHP said.

It is still unclear who had the green light, but both Leiva and Morales entered the intersection at Marsh Creek Road simultaneously, and Morales' Acura T-boned Leiva's Honda. Both cars came to a stop just west of the intersection.

Both Mauel Morales and Leiva only suffered abrasions and were transported to a local hospital for treatment.

Oscar Morales, however, suffered major internal injuries and had to be airlifted to John Muir Medical Center in Walnut Creek to undergo surgery, according to CHP.

As of 4:15 p.m. Tuesday, CHP said Oscar Morales was out of surgery and was expected to survive.

CHP added that all parties were wearing seatbelts at the time of the accident.

Traffic was not severely affected as a result of the collision, CHP added.

Contact Katie Nelson at knelson@bayareanewsgroup.com. Contact Rick Hurd at rhurd@bayareanewsgroup.com.