FORT MYERS, Fla. -- The last two times the Red Sox have faced an ace lefty -- Saturday at home against Braves ace Chris Sale and Tuesday on the road vs. Yankees prized free-agent acquisition Max Fried -- first baseman Triston Casas has been in the starting lineup.

This isn’t a coincidence.

“He will play. He’s going to play against lefties and righties," said Red Sox manager Alex Cora. "We’re not going to platoon at first base."

For the 25-year-old slugger, this is the next natural step in his evolution. And Casas is embracing it.

He certainly seemed to be when he hammered an opposite-field homer against Sale in his first at-bat on Saturday, then laced a single off the base of the replica Green Monster in his second turn at the plate.

“It means a lot,” said Casas. “I’ve been waiting my entire life for this opportunity. Throughout the Minor Leagues, even my first couple years in the Majors, I’ve been learning from a lot of the veterans how to go about playing every day, and I think it's culminating into a perfect storm for me to be able to handle that opportunity. And I'm excited for the challenge.”

It is a challenge Casas was set to receive last season, only to tear cartilage in his left rib cage, forcing him to miss four months of the season. When he returned in late August, Casas had trouble regaining his timing at the plate and sat against a lot of lefties down the stretch.

He has spent the past several weeks trying to become a player the Red Sox can expect production out of, no matter what hand the opposing pitcher throws with.

“I think everything's trending in the right direction, and I feel like my comfort level against lefties increases every single at-bat,” Casas said. “It's only going to keep getting better as the time passes, including my work in the cage -- just emphasizing different types of angles and making little adjustments to my swing. All those things combined are going to help increase the overall numbers against left-handed pitching while still keeping the main goal, which is to hit all types of pitchers.”

In 183 career plate appearances against lefties, Casas has a slash line of .227/.350/.422 with seven doubles, seven homers and 17 RBIs.

The on-base percentage proves that Casas already has a history of solid pitch recognition against southpaws, so the next step will be to add more production.

“He’s been working hard with [hitting coach] Pete [Fatse] to solve that,” said Cora. “If you look at the numbers throughout his career, he’s not great [against lefties], but we do believe he can do it and this is the time just to let him be and see where it takes us.”

Casas -- who has massive raw power -- is using every tool at his disposal to make himself a threat against lefties.

That includes the revolutionary Trajekt pitching machine, which has the ability to simulate individual Major League pitchers on demand. Casas has been using it regularly at the Fenway South complex and will continue to do so when the club returns to Boston for the start of the season.

“Thankfully, there's so many different tools in there and different technology to be able to simulate the type of movement that I'm going to be facing come game time, especially in big situations -- getting set up [by pitchers], matched up [by opposing managers] -- so I’m looking forward to big-time at-bats late in games,” said Casas. “And I'm excited for it.”