"It was better than the first two games, that's for sure," Luck said. "It was much improved on putting two halves together."
It was Jacksonville's fourth consecutive double-digit loss and the 21st in the team's last 35 games - all since owner Shad Khan took over in 2012.
This one was over early thanks to Luck's near-flawless first half. The rising star completed 22 of 27 passes for 244 yards before the break, connecting with nine different receivers. He found Ahmad Bradshaw for a 6-yard touchdown that made it 10-0, hooked up with Dwayne Allen for a 1-yard score on the next drive and capped the impressive start with a 7-yarder to Coby Fleener.
Jacksonville's quarterback change came much earlier - and was a switch that coach Gus Bradley expects to be permanent.
"The biggest thing for me is to just keep my head held high and try to be the captain that I was voted to be for this year and help Blake out as much as I can and really try to help this offense grow," Henne said. "He was drafted for this moment, and I understood it from Day 1. We had to do some really good things at the beginning of the year for keep my job.
"I hope he plays really well. I'm really pulling for him, and I'm going to be his biggest cheerleader on the sideline."
"It was definitely good to go out there and not be like, 'Oh my God, what am I doing here?'" Bortles said. "It was good to get out there and get that experience."
Indianapolis made plays from start to finish, including Greg Toler's 47-yard interception return for a touchdown with 2:58 to play.
Luck did most of the damage, though.
Jacksonville allowed 330 yards in the opening half - 529 for the game - and contributed to its woes with missed tackles and blown assignments.
Indy's defense also came up big, finishing with four sacks.
"We wanted to make a statement, put it out there on film, that we able to rush the quarterback, that we can pressure them," linebacker Erik Walden said. "We put an emphasis on it. We've heard it from the media, we heard it from the coaches, so we wanted to make our statement that we are capable of playing like this week in and week out."
The Colts forced three three-and-outs on Jacksonville's first three drives. Henne started getting booed, and Bradley eventually made the switch.
Henne completed 4 of 7 passes for 33 yards and was sacked three times.
Bortles was considerably better and even kept most of the crowd from leaving the home opener, which featured the debut of $63 million in stadium upgrades that include a party deck, two pools and cabanas.
"He brings excitement," Shorts said. "He's a first-round guy for a reason, first quarterback chosen for a reason."
NOTES: Colts WR T.Y. Hilton (ankle) and LB Andy Studebaker (hamstring) left the game and did not return. ... Luck is first Colts QB since Johnny Unitas in 1967 to complete at least 75 percent of his passes for 350 yards, with four TDs and no INTs, in a game. ... Jaguars have been outscored 119-27 since leading Philadelphia 17-0 at halftime in the season opener.