After landing on his head during a team practice on Monday, Dallas Mavericks center Chris Kaman suffered a concussion, and there’s no timetable for his return (though the big man hopes to be back soon.) Per the Dallas Morning News: “It all happened real fast,’ he said. ‘I landed on my head from like 3 feet in the air. It hurt. I was dizzy a little and my vision’s been a little blurry. And I’ve had a headache for the last two days, plus my neck is killing me.’ When Kaman failed the NBA’s concussion test, he was ruled out of Tuesday’s game against Portland. ‘They just want me to take it easy,’ he said. ‘It’s not the first one that you worry about, it’s the next one. They have the test and I didn’t pass that. It involves a deck of cards. I was a lot worse than I did at the beginning of the year, so they failed me. I feel a little foggy. I’d rather not risk getting hit again.’ [...] Asked if he’d ever had a concussion before, Kaman said: ‘Maybe, but they didn’t test for it before. I would have just played.’”