Aaron Sanchez came into spring training this year with a different mentality than in the past.

For the first time in his major-league career, the 24-year-old right-hander doesn't have to prove he's worthy of a spot in the Blue Jays' starting rotation after his dominant season last year. He's using that lack of pressure to sharpen his arsenal.

"The last few years I've come in having to compete for a spot," Sanchez said Wednesday after his first official workout of the spring. "This year I have the luxury of [getting] to work on things. I feel like I made tremendous strides with my curveball last season and even in the off-season so my focus this year is on the change-up."

Sanchez threw his change-up just 270 times in 2016 — or nine per cent of the time — striking out 10 batters with it, but also giving up seven hits including a home run.

"I don't want to get too caught up in it," he said. "Just enough to have that comfort with it to take it into the regular season."

Toronto's anchor

Sanchez helped anchor Toronto's rotation last year, going 15-2 with an American League-best 3.00 earned-run average. And he did it while on an innings limit.

Wanting to protect their young pitcher's valuable arm, the organization debated sending Sanchez to the bullpen midway through the season. His performance in the rotation, however, made the decision more difficult.

In a compromise, Toronto opted to manage his innings by skipping a few of his starts.

Sanchez finished the regular season with 192 innings (plus 11 2/3 in the post-season), more than doubling his 2015 total (92 1/3) when he was used as a reliever for the second half of the year.

"I think last year I showed limitations shouldn't be an issue," Sanchez said. "I'll leave that up to management and how they feel but I'm ready to go. I put the work in and I'm excited to see how this year shakes out."

Blue Jays manager John Gibbons said he wasn't worried about Sanchez's innings this season.

"Yeah, I don't see any limitations," Gibbons said. "He ended up throwing a full year last year. He's a big strong kid, he worked really hard this winter. We're going to monitor him here in spring training and back him off a little bit ... we'll keep an eye on that but he's good to go. No concerns."

Sanchez came into spring training last year with 25 pounds of muscle added to his frame. While he lost about 15 pounds over the course of the season — he blamed that on travel and the playoffs — he's back up to his 2016 pre-season weight of 220 pounds.

'It's fun to me'

He's proud of where he's at now.

"My job is to come to the field and work out," Sanchez said. "Obviously my regimen was the same as last year — gain as much as I possibly can. I finished the season a little bit lower than I did entering it, it's a little bit of a grind.

"That's the enjoyable part of this, noticing changes in your body and working hard. It's fun to me."

Sanchez will join fellow right-handers Marco Estrada and Marcus Stroman and lefties J.A. Happ and Francisco Liriano in a starting rotation that sees all five pitchers returning from 2016. Liriano, acquired by Toronto in a late-season trade, replaces knuckleballer R.A. Dickey, who signed a free-agent deal with Atlanta in the off-season.

The 2016 rotation, which seemed unspectacular heading into the season, ended up being the Blue Jays' strength.

Sanchez hopes the 2017 version can be just as good.

"That was one of the areas that a lot of people doubted us," Sanchez said. "We took that with some fire underneath us and we tried to prove to some people that we were for real about this.

"I think it's something we'll try to continue from last year. Everybody worked extremely hard with this group and hopefully we can stay healthy like last year and proceed to do the same if not better."