During an offseason mostly defined by additions, the Blue Jays’ de facto replacement for the one star they lost has to be feeling the heat.

Longtime Blue Jays All-Star shortstop Bo Bichette signed with the New York Mets as a free agent, and by that point, the Blue Jays had already signed 29-year-old Japanese infielder Kazuma Okamoto, who will make his major league debut next month as the club’s likely opening day third baseman.

If it sounds like a pressure-filled situation for Okamoto as he joins the defending American League champions, it’s worth noting that the experts seem to see it the same way.

On Monday, MLB.com Blue Jays reporter Keegan Matheson named Okamoto as the player with the “most to prove” of anyone on the roster this spring.

“Replacing Bo Bichette will require an effort from a half-dozen different players, but none more than Okamoto, which is an unfair expectation to thrust upon the Japanese star making the move to Major League Baseball,” wrote Matheson.

“Okamoto will need to adjust to MLB pitching quickly, and depending on how the Blue Jays deploy Addison Barger, Okamoto could see significant playing time at third base. On a roster that’s fairly set on the position player side, Okamoto is the ultimate variable here, capable of elevating this entire lineup if he carries over his long track record of success from Japan.”

In 11 seasons in Japan’s Nippon Professional Baseball, Okamoto slugged 277 home runs and put up an OPS of .882. Those numbers improved drastically starting in his age-22 season, and last year, he fought through injury to post a .992 OPS and 15 home runs in 77 games.

The Blue Jays don’t need Okamoto to be the sort of lineup-anchoring bat he was in Japan. But after losing Bichette, they also can’t afford too many growing pains from the newcomer if they want to repeat as American League East champions.

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