GLENDALE, Ariz. -- Through three-plus weeks of Arizona Fall League play, Grant Lavigne had accomplished basically everything offensively, including being the rare first baseman to pick up a triple and a steal. All he had left to do was homer.

So on Thursday, that’s just what he did.

The Rockies’ No. 13 prospect went deep in the third inning to extend his season-opening hitting streak to an AFL-best 12 games in Salt River’s 9-6 win over Glendale at Camelback Ranch.

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Lavigne, who finished 2-for-4 with a walk and two RBIs, crushed a 1-0 sinker from Desert Dogs right-hander Tanner Dodson out to right-center to give the Rafters a 6-0 lead to begin the third inning. The ball traveled 457 feet, per Trackman, and had an exit velocity of 106 mph off the left-handed slugger’s bat.

“I was facing a sinker-slider guy, so I was trying to pull him inside and look for something in,” Lavigne said. “If I got something in, it was going to end up middle, so that was my approach in that at-bat.”

Not only is Lavigne's hitting streak the longest in the Fall League this season, but no other streak comes close. Tyler Hardman’s six-gamer for Mesa, which was also extended Thursday night, is the second.

Thursday’s performance pushed Lavigne’s Fall League line to .386/.471/.636 through 51 plate appearances.

Late-coming power could be a theme for the 2018 42nd overall pick out of New Hampshire.

Lavigne, 23, has long drawn solid reviews for his ability to show a discerning eye at the plate and produce impressive walk rates. He said Thursday, however, that he’s tried being more aggressive early in AFL at-bats (for example, a 1-0 count) to find more hits.

However, unlike many prospects at his position, he hadn’t shown a ton of in-game pop and didn’t cross into double-digit home-run territory until this summer when he hit 10 dingers in 125 games between High-A Spokane and Double-A Hartford.

One of the main culprits for Lavigne’s lack of over-the-fence power, despite his size at 6-foot-4 and 220 pounds, has been a lack of lift in his swing, resulting in ground ball rates right around 50 percent throughout his career. Over 242 plate appearances with Hartford, it was a career-high 56.4 percent, and that Eastern League experience made Lavigne’s Fall League main objective clear.

“It starts with your preparation and work in the cage,” he said. “It’s the focus on getting the ball in the air and keeping it off the ground.”

Lavigne’s hitting streak comes at an important time in his young career. As a prep pick four years ago, he will be Rule 5-eligible for the first time this offseason, and the Rockies will need to add him to the 40-man roster or else leave him open to that process. That puts Lavigne in the position of either proving his roster worthiness to his current parent club or his Major League readiness to the other 29 organizations.

Any talk of that status wasn’t made explicit between Lavigne and Colorado before the Fall League, the prospect said, and besides between launch angle and now the continuation of his early hot streak, he has enough to keep himself busy in the desert.

“They sent me here, and obviously I have to work on some things,” Lavigne said. “I’m just taking advantage of it.”

D-backs catcher Cooper Hummel went 2-for-3 with a homer and four RBIs for Salt River in his final game of the Fall League. Reds No. 18 prospect Rece Hinds struck a 117 mph RBI triple as part of a 2-for-5 showing for the losing Desert Dogs.