LOS ANGELES (AP) After just one game in new coach Sean McVay's system, the change in Jared Goff was striking.
No longer an uncertain rookie hiding behind a lousy offensive line, Goff flung the ball confidently around the field for the Los Angeles Rams. He shook off his mistakes and made smart adjustments on the way to the biggest passing day of his young career - and his first victory as a starter.
McVay got a big-time game out of last season's No. 1 pick during the Rams' 46-9 rout of the Indianapolis Colts on Sunday, but Goff was just one of several impressive performers in a season-opening stunner.
''Starting off the season with a win, regardless of if it's my first or Sean's first, I think it's exciting for everybody,'' Goff said.
Goff went 21 of 29 for a career-high 306 yards and a touchdown for the 31-year-old McVay, the youngest head coach in modern league history. Their partnership is in its infancy, but the early results were awfully promising.
''I thought he took good care of the football, made good decisions, and he did seem to have good command of it,'' McVay said of Goff, who went 0-7 as a starter last season. ''I'm very proud of him. Thought he did a great job, and it was awesome for him to get his first win.''
The entire afternoon was a welcome reversal for the Rams, who lost six straight home games and their final seven games overall to end last season amid dwindling Coliseum crowds.
The Rams returned with their highest-scoring performance since November 2014 in their first game since McVay took over a franchise that went 4-12 in its 13th straight non-winning season and 12th straight non-playoff season.
''When McVay got here, he raised our accountability level, our standards,'' linebacker Robert Quinn said. ''And I think guys are having fun. Of course we're looking for improvements every week, but it's a good place to start.''
McVay is just eight months into the Rams' rebuilding project, and he was quick to acknowledge their fortunate break with the injury absence of Colts quarterback Andrew Luck. The Rams will take any advantage they can get if it helps to put their season on track.
''We know it wasn't a perfect game, but there were a lot of things that the players did a great job with,'' McVay said.
Cooper Kupp's first NFL touchdown catch put the Rams up 24-3 in the second quarter. That's a bigger lead than the Rams held at any point over the past two seasons in St. Louis and Los Angeles, when they had the NFL's worst offense.
Todd Gurley rushed for a score and added 56 yards receiving while Los Angeles roared to a 37-3 lead in the third quarter. Goff didn't throw an interception, and he hit newcomer receivers Kupp, Sammy Watkins and Robert Woods for a combined 12 catches for 187 yards.
Even with All-Pro lineman Aaron Donald missing the first game of his four-year career, Los Angeles' defense feasted on fill-in Colts quarterback Scott Tolzien. Trumaine Johnson intercepted Tolzien's first pass and returned it 39 yards for a touchdown, while Lamarcus Joyner returned another pick 29 yards for another score in the third quarter.
''You always feel guilty when you let your team down,'' Tolzien said. ''(We've) got a lot to improve on, starting with me.''
New Rams defensive coordinator Wade Phillips' unit also had a memorable debut, holding the Colts to 225 yards, getting four sacks and adding a fourth-quarter safety to its two interception returns.
''We wanted to show that this is not a rebuilding year,'' defensive lineman Michael Brockers said. ''We're ready to go.''
Tolzien passed for 128 yards in his fourth career NFL start in place of Luck, who wasn't ready to return from a right shoulder injury.
From the disastrous opening drive to an inept fourth-quarter safety, the Colts weren't competitive without their leader . Indianapolis also played without center Ryan Kelly and top cornerback Vontae Davis.
''Obviously, we were dominated in this football game in all three phases,'' Indianapolis coach Chuck Pagano said. ''Outcoached in this football game. It's my responsibility, and it falls on me.''
HIT THE SHOWER
McVay could sense his players were coming for him with the Gatorade bucket in the final minutes, but he grinned and accepted his fate.
''I could have avoided it if I wanted to, but I felt like I kind of had to take it a little bit,'' McVay said after changing out of his soaking-wet shirt.
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