The Lotte Marines 20-year-old pitcher Roki Sasaki said he enjoyed basking in the afterglow of his perfect game — Nippon Professional Baseball’s first in 28 years — but woke up ready for a fresh start on Monday. “The reality is slowly starting to sink in. I spent last night immersing myself in the experience,” Sasaki said of his heroics on Sunday. “That mark in history will always stand. A player is expected to perform throughout the season so I’m shifting gears and moving on,” he said after an hourlong training session which included core exercises and sprints. On Sunday afternoon at his tea…