Leg injury may put Rodney McGruder out for the season.

KANSAS CITY — The Miami Heat’s injury-free training camp hit a sobering detour with the team confirming that potential starting small forward Rodney McGruder has a stress fracture of his left tibia (lower leg). He is expected to undergo surgery Tuesday.

While the team said “any timetable is premature,” Yahoo Sports reported that McGruder will be sidelined for three to six months, a timetable that could have him out for the season.

McGruder, 26, had been complaining of leg soreness for the past several days, despite soldiering on in his regular role.

McGruder was the lone Heat player to start all five exhibitions, with the Heat’s preseason concluding with a game tonight at the Sprint Center against the Philadelphia 76ers.

Heat coach Erik Spoelstra did not mention the McGruder injury before the Heat’s departure for Kansas City, with the team next to convene at today’s shootaround.

With McGruder sidelined, the Heat likely will roll out a lineup for Wednesday’s regular-season opener against the Orlando Magic at the Amway Center that has not started during the preseason, with point guard Goran Dragic remaining behind in South Florida for the arrival of his family from Europe on Thursday night.

Spoelstra’s options as his starting small forward include Josh Richardson, who has had the strongest preseason of any Heat

player, as well as Justise Winslow and James Johnson.

Another option at small forward, second-year wing Okaro White, is sidelined with a strained left shoulder.

“It’s just a tweak, a mild sprain,” Spoelstra said after Thursday’s practice at AmericanAirlines Arena. “Thankfully, he got everything checked out.”

With so many absences, Spoelstra said he expects more playing time for center Hassan Whiteside and guard Dion Waiters in Friday’s preseason finale.

McGruder holds a $1.3 million salary for the coming season that becomes guaranteed if he is on the opening-night roster. His guarantee for the coming season currently stands at $453,000.

Teams must trim to a maximum of 15 players by Monday, with most of those machinations having to be completed by Saturday because of the NBA’s 48-hour waiver period.

McGruder’s 65 starts last season were the fifthhighest total by a rookie in franchise history. His 10-game streak with at least one 3-pointer last season was the third longest by a Heat rookie.

The Heat have largely gone with a 10-player primary rotation during the preseason, with McGruder the lone player locked into a specific role. While Richardson is equipped to play small forward, he has started the past three games at point guard with the team giving Dragic time off following a hectic September playing for Slovenia at EuroBasket.

McGruder played 25 minutes in Wednesday’s preseason victory over the Washington Wizards at AmericanAirlines Arena, with Spoelstra opting to give Dragic, Waiters and Whiteside the night off.

McGruder stands among the most popular players in the locker room for his perseverance of going undrafted out of Kansas State, moving on to play in Hungary and then working his way into the NBA through time with the Heat’s developmentalleague affiliate, the Sioux Falls Skyforce.

McGruder consistently had downplayed during the preseason the possibility of emerging as the Heat’s opening-high small forward, willing to fit into any role offered.

“I’m out there to do whatever needs to be done to help my team to win,” he previously said. “So if I come off and there’s something for me, I’m going to be ready to shoot. Or if it’s a pick-and-roll for me, I’m ready in that situation, as well.”

Spoelstra has said the growth in McGruder has been pronounced, even since last season’s rookie breakthrough.

“We see somebody that will not be denied,” Spoelstra said recently. “He’s proven himself with us. As we’ve gotten to know him, from him helping us win a [development-league] championship in Sioux Falls, but also breaking into a rotation and starting for us, so many games last year, he’s a winner. And he’s so committed, every single day, consistently working diligently to improve.”

Mitchell in, Drew out

The Heat signed forward Tony Mitchell on Thursday and waived guard Larry Drew II.

Mitchell has averaged 21.2 points, 5.9 rebounds and 2.8 assists in 78 NBA G League games, making 52 starts. In 2013, he was named developmental league Rookie of the Year. Mitchell has spent the last three seasons playing overseas.

Drew, who was signed Sept. 5, appeared in one preseason game and had one rebound, one assist and a steal in five minutes on Oct. 5 at Brooklyn.

McGruder