In less than a calendar year, Josh Roberts went from a starter to a rarely used reserve and a starter again. He underwent major shoulder surgery. He contracted COVID-19 in March, losing his sense of taste and smell.

“It’s been a crazy year,” the St. John’s junior forward told The Post in a phone interview.

In this roller-coaster ride of a year, the last few months have been predictably up and down. Roberts, after starting 28 games a year ago, came off the bench in the opener and started the second and third game of the season. From then on, his role vanished. In a span of nine games, he played a grand total of 42 minutes. He didn’t even get off the bench in a loss at Xavier.

“It was a tough time for me, I’m not going to lie,” he said.

When the media asked coach Mike Anderson about Roberts, he would tell reporters the forward would be needed. He told the 6-foot-9 Roberts the same thing: Stay ready, keep practicing hard. He would put in extra work after practice. His aunt, fitness instructor Geri Gonsalves, called him every night with a similar message of not losing faith in himself.

“I just learned to stay positive and not get down on myself, don’t think negative thoughts,” Roberts said. “It’s not going to get you anywhere.”

Finally, his time came two weeks ago. He got the start against Butler and produced eight points and three rebounds in a season-high 23 minutes. St. John’s (9-7, 3-6) won, limiting the Bulldogs to 57 points. Four days later, Roberts was again a factor, registering four blocked shots in a two-point loss to Marquette. He was vital in wins over UConn and Utah Valley, again in a starting role.

St. John’s enters Wednesday’s trip to DePaul playing its best basketball, winning three of its last four games. It has found its defense again, holding the opposition to 69.5 points per game, 43.5 percent shooting from the field and 33.8 percent shooting from 3-point range over the last four games. Roberts has been essential, providing a rim-protecting presence that was sorely lacked. He’s also shown a soft touch around the basket, averaging 5.5 points these last four games, to go along with 2.2 blocks.

“It feels great to know that the hard work I put in is paying off — not just for me, but us as a team,” he said.

Roberts admitted he was frustrated by his lack of playing time, though he did understand it somewhat. He was working his way back from shoulder surgery. The first month he had to practice with a shoulder brace that limited his range of motion and made it difficult to dunk. More recently, a groin issue hampered his progress. When he really got down he leaned on teammates Marcellus Earlington and Greg Williams Jr., the juniors with whom he arrived at St. John’s. As freshmen, all three spent most of the time on the bench, and they developed a bond.

“After the games, we would go back home and just talk,” Roberts said. “They would say, ‘Stay positive, bro, your time is going to come. We need you.’ That really helped me get through it.”

Now Roberts is just thrilled with the opportunity he has. He’s worked his way back into Anderson’s good graces. He’s impacting games. But the Alabama native feels there is so much further he can go.

“I know,” Roberts said, “I’m not playing my best yet.”