It’s been 20 years since Hideki Matsui made his Yankees debut, and before his clutch hitting over six postseasons vaulted him to a place among the greats in the organization, there was a time as a rookie when Matsui was a slumping slugger, struggling to live up to wild expectations.

Through June 4 of his first season after coming over from Japan, Matsui had played 58 games and hit just three homers — one of them a memorable grand slam in his Yankee Stadium debut — with a .250 average and an anemic OPS of .656.

Then came June 5 in Cincinnati, where Matsui picked up his first four-hit game in the majors with three doubles and a homer.

And a few weeks later, Matsui further cemented himself as a force in the middle of the Yankees lineup with a volcanic showing while playing in both ends of a historic day-night Subway Series doubleheader split between Yankee and Shea Stadiums, following the first such twinbill in 2000.