Denver Nuggets reserve forward Juancho Hernangomez has been diagnosed with mononucleosis, the team announced Tuesday.

Hernangomez, a second-year player out of Spain, was officially ruled out of Monday’s loss to the Wizards with an undisclosed illness and did not travel with the team for Wednesday’s contest at Charlotte. Symptoms for mono, which include fatigue, sore throat and fever, typically last four-to-six weeks.

This helps explain Hernangomez’s slow start to the season. He had had played in 13 total minutes over Denver’s first two games and did not record a stat. After the Nuggets’ season-opening loss at Utah last week, Nuggets coach Michael Malone said Hernangomez needed to “get it going.”

“Right now, he doesn’t have that same energy and zap that he had last year,” said Malone, adding Hernangomez had a grueling offseason while playing for the Nuggets in summer league and for Spain in EuroBasket.