For center Justin Hamilton, being drafted by the Heat last month was so unexpected, so surreal, that when he woke up the next day, “I wasn’t sure the draft really happened.”

But Hamilton’s chances of making the Heat — which were iffy at best to start with — have taken a blow this week because of a slight hamstring strain that has sidelined him for the first two games of the Heat’s Las Vegas Summer League schedule, including Monday’s 106-56 victory against the Los Angeles Lakers.

It was the largest margin of victory in NBA summer league history.

The Heat has 13 guaranteed contracts, and one of the final two roster spots likely will go to a center who can provide more depth behind Chris Bosh, Joel Anthony and Dexter Pittman. Two of the internal candidates — the 7-foot Hamilton and 6-9 Jarvis Varnado — are both out with injuries but could play at some point this week.

Another internal candidate, 6-11 Mickell Gladness, likely has the best chance of the three. Gladness, who appeared in eight games for the Heat and 18 for Golden State this past season, has played well so far: seven points, five rebounds and a block in 15 minutes Sunday against Toronto and 10 points, three rebounds and three blocks in 18 minutes against the Lakers.

There’s also a decent chance the Heat instead might opt to sign a veteran center at the league minimum salary. Ronny Turiaf would be an option to return if he cannot find a better offer elsewhere.

Other veteran centers who could be in line for minimum deals include Jermaine O’Neal; Nazr Mohammed; Jason Collins; Eddy Curry (who played only 83 minutes for the Heat last season); Hamed Haddadi; Daniel Orton; Tony Battie; Ryan Hollins; Joel Pryzbilla; and Kyrylo Fesenko.

Former No. 1 overall draft pick Greg Oden, recovering from a fifth knee surgery, has interest in the Heat, but Miami has not called to inquire, according to his agent, Mike Conley. Oden would like to play at some point next season but isn’t sure of a timetable, Conley said.

Hamilton, drafted 45th overall, impressed the Heat during workouts last week before being sidelined by the hamstring.

“He’s a highly intelligent player, maybe a little more skilled than I thought he was from a passing standpoint and being able to run offense through him,” said Heat assistant David Fizdale, who is coaching Miami’s summer league team.

Fizdale likes Hamilton’s “motor, ability to bang and be physical, his toughness, his screening and IQ. With his work ethic and ability to go with either hand and the fact he can step out and shoot the ball — all of those things together give him a chance to be pretty good. He’s got a ways to go to score in the NBA on the block.”

Heat president Pat Riley said Hamilton “is not an above-the-rim player” but “has a nice touch from 15 feet.”

Even before the injury, Riley acknowledged the Heat might stash Hamilton in Europe for at least a year.

For perspective, former Memphis forward Robert Dozier (selected by Miami with the 60th pick in 2009) and Varnado (picked 41st by the Heat in 2010) are still awaiting their NBA opportunity.

Like Varnado and Hamilton, Dozier also has missed the first two summer league games with an injury.

Hamilton averaged 6.4 points and 5.4 rebounds as a sophomore at Iowa State, then transferred to LSU, where he averaged 12.9 points, 7.2 rebounds and 1.3 blocks as a junior before graduating with a sociology degree and turning pro early. But he wasn’t listed among ESPN’s top 100 draft prospects.