SAN DIEGO (AP) Philp Rivers is in his 11th season in the NFL, and his ninth as a starter.
Blake Bortles is a rookie who made his first start.
Rivers threw for 377 yards and three touchdowns, two to Eddie Royal, and the Chargers turned back an early scare from Bortles and the winless Jaguars.
Passing more because the Chargers' running game is nonexistent due to injuries to Ryan Mathews and Danny Woodhead, Rivers had his second three-touchdown game of the season. He went 29 of 39. His passer rating was 130; last week it was 131.4 in a 22-10 win at Buffalo.
''We weren't as balanced but we were rolling pretty good in the passing game,'' Rivers said. ''We spread the ball around today and that was pleasing. It was a collective effort.''
Bortles played well for the most part, especially in the first half. He threw one touchdown pass, was intercepted twice and twice had Jacksonville (0-4) in the lead in the first half.
Bortles was 15 of 18 for 149 yards in the first half, which ended with San Diego up 17-14. He finished 29 of 37 for 253 yards.
''I thought we had a decent first half and we have to continue to carry that over to the second half,'' Bortles said.
That's where things fell off for the Jaguars. It was the fifth straight game the Jaguars lost by double digits, dating to last season's finale. They've been outscored 152-58 this season.
The Chargers (3-1) extended their winning streak to three.
Here are some things that stood out Sunday:
ROYAL EFFORT: Royal had scoring catches of 47 and 43 yards, his second straight two-touchdown game.
''We saw some things on film that we wanted to take advantage of,'' Royal said. ''We were throwing the ball well today. Philip looked great. You never know who is going to get the ball. It just happened to be me the last two weeks.''
VETERAN PRESENCE: Although the Chargers looked out of synch at times, Rivers helped keep it together.
After Toby Gerhart gave Jacksonville a 7-3 lead on a 1-yard run early in the second quarter - the Jaguars' first TD rushing since Nov. 24 - it took Rivers and the Chargers only five plays to answer. Rivers noticed linebacker Geno Hayes covering Royal, who got wide open for a 47-yard reception to put San Diego up 10-7.
ROOKIE SMARTS: Bortles then took advantage of a breakdown in coverage when he completed a 44-yard pass to Allen Hurns, who made a tumbling catch at the Chargers 2. Bortles found Nic Jacobs in the end zone on the next play.
Two drives later, Royal found a seam in coverage on third-and-10 from the 43, hauled in Rivers' pass and outran the coverage to put the Chargers ahead 17-14 a minute before halftime.
MORE BORTLES: The Jaguars turned to Bortles at halftime of a blowout loss to Indianapolis a week earlier. He was the fifth Jaguars QB to start a game during his rookie season. All five lost their first start.
He was intercepted by Flowers in the third quarter at the Jacksonville 40, setting up Nick Novak's 34-yard field goal for a 27-14 lead.
''He's a great quarterback,'' said San Diego cornerback Brandon Flowers, who had an interception. ''He has a strong arm. He came out like, firing. Did a great job of moving the offense. We just had to get settled in, show them one thing and play another thing. We did a great job on trying to disguise.
''I think he's going to be a real good quarterback in the league.''
RUNNING ON EMPTY: The Chargers ran for only 42 yards.
''We don't have a choice. We have to get better,'' coach Mike McCoy said. ''The way we are throwing the ball we are going to keep throwing it.''
Mathews is out indefinitely with a knee injury and Woodhead is out for the year. Rookie Branden Oliver was San Diego's leading rusher with 23 yards on nine carries.
Novak finished with four field goals for San Diego.
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