His first carry went for no gain and the next carry netted minus-3 yards. At the end of the first half, Barkley had 12 yards rushing on eight carries, an average of 1.5 yards per attempt.
The Jaguars defense, a unit that finished the 2017 season ranked second overall in total defense, deserves a lot of the credit for keeping Barkley in check.
"It definitely was a challenge and a challenge that I was excited for and excited to go against and it definitely was a test," Barkley told reporters after the game, via the Giants' official website. "Not just the defensive line, but their defense as a whole."
Barkley's patience, however, paid off in the second half. He settled down and totaled 10 carries for 94 yards and a touchdown, which came on a 68-yard burst off right tackle.
"It was a great call, first of all, and it was blocked up perfect," Barkley told reporters. "The O-line did a great job on the front side creating movement. [Tight end] Evan [Ingram] did a great job on the backside with a cut block and I was able to get one-on-one with the guy, make him miss and use my speed on the sideline to get in the end zone."
The explosive touchdown run showed why the Giants used the second overall pick on Barkley.
"It was a great run," coach Pat Shurmur told reporters during his postgame press conference. "That's why we drafted that young man."
Barkley attributed his second-half success against the Jaguars to staying within himself with an understanding not every offensive call will result in a big play.
He also trusted his blockers while adjusting to the flow of the matchup.
"Your mindset changes throughout the game because you get a feel for it," Barkley said. "You get a feel for the O-line, you get a feel for what their defense is doing, how they're attacking you, how they're playing."
While the Giants ultimately lost to the Jaguars by a 20-15 score, Barkley's debut -- 106 yards rushing and a touchdown on 18 carries and 22 yards receiving on two catches -- offered plenty of optimism for the offense.
He struggled early in the first half against a stout defense and failed to convert a 2-point conversion attempt, but Barkley's ability to get it going in the second half proved the Giants' ground game is primed to improve after finishing the past two seasons ranked near the bottom of the league.
"I think that you see the potential that we have on this offensive side of the ball as a team," Barkley told reporters, "and we just have to eliminate the mistakes and I have to eliminate my mistakes."