What a difference a year makes.

A year ago at this time, the Toronto Blue Jays’ rotation was a mess.

It was Hyun Jin Ryu, a pair of reclamation projects with fairly low expectations in Robbie Ray and Steven Matz, and a collection of prospects and depth arms.

It was the clear Achilles heel for a team that looked like it could be an offensive juggernaut (it was).

But things changed quickly last summer, and that has continued over the winter.

Ray and Matz proved the front office right in so many ways, Alek Manoah arrived in May, registered a 3.22 ERA as a rookie and never looked back, while the José Berríos blockbuster added a proven top-of-the-rotation arm.

That foursome was stellar down the stretch, and the rotation was the reason the Jays surged over the final two months and came within one game of a post-season spot.

Fast forward to today and the names have changed since the final day of the 2021 season, but the impact that this rotation is expected to have has not.

Berríos, Manoah and Ryu return, but general manager Ross Atkins just finished spending $146 million this winter to replace Ray and Matz.

After giving longtime Jays front office favourite Kevin Gausman $110 million back in November, the Jays found a Matz replacement on Saturday, inking former Seattle Mariners left-hander Yusei Kikuchi to a three-year, $36-million contract.

Like Gausman, who the Jays pursued on a couple of occasions, the Japanese-born Kikuchi was a pitcher Atkins had inquired about before he inked a three-year, $43-million deal with the Mariners prior to the 2019 season.

Over those three campaigns on the West Coast, Kikuchi finished with an underwhelming 4.97 ERA, while also struggling with the gopher ball at times, as he gave up 66 homers over 70 career starts.

Inconsistent command has also been an issue for the 30-year-old lefty, but the Jays believe they’re handing veteran pitching coach Pete Walker an arm with intriguing upside.

The 2021 season was Jekyll and Hyde.

Kikuchi earned a trip to the All-Star Game in the first half thanks to a 3.48 ERA and a rising strikeout rate, but he absolutely cratered in the second half with a 5.98 ERA, giving up so many scorchers that he finished near the bottom of the league in average, exit velocity allowed and hard-hit percentage.

While they’re much different pitchers, it’s an eerily similar profile to Matz, who flourished with the low expectations at the back end of the Jays rotation and it earned him $44 million over four years with the St. Louis Cardinals.

At the very least, the Jays have built up some starting pitching depth.

With Kikuchi bringing up the rear behind Berríos, Gausman, Manoah and Ryu, Ross Stripling will now shift into a swing-man type role, while Nate Pearson can either stay stretched out at Triple-A Buffalo — consistent innings are needed — or the Jays can simply shift their former top prospect to the bullpen and hope to get 80 big-league innings out of him in 2022.

Some hybrid of that is the likely outcome in the end, but Pearson has to stay healthy first.

With camps getting underway in earnest around baseball this week, the Jays are still looking to add.

Now that a No. 5 starter is checked off this list, the infield situation is likely to be addressed, and soon, with opening day just 27 days away.