What does Kevin Gravel admire most about the Kings’ defenseman who comprise one of the NHL’s stingiest units? “Whether they have a good game or a bad game, they move on and forget about it,” he said. “They always keep an even keel.” The current circumstances for this young Kings defenseman are decidedly uneven. A roller coaster of emotions is likely a more apt description for Gravel’s training camp experience. Gravel, 25, spent all but six games at the NHL level last season, a graduation of sorts for the versatile defenseman who previously had just five NHL games under his belt. By the end of training camp, which began Sept. 13, he may find himself back with the Kings’ American Hockey League affiliate in Ontario, again. The most telling evidence of this possibility was Gravel’s absence from the Kings’ 26-man roster that traveled to China for a pair of preseason games. His competition is stiff for the few open spots behind Drew Doughty and the other two-time Stanley Cup champions who comprise a Kings defense that allowed the sixth-fewest goals in the NHL last season. There is even a factor working against Gravel that has nothing to do with on-ice performance. He is waiver-exempt, meaning he can be moved in and out of the minor leagues more easily than his non waiver-exempt competition, young defensemen Christian Folin and Kurtis MacDermid. “Certain things are out of your control, so as long as you leave it all out there and make the decision hard on them, there’s nothing you can hang your head about,” Gravel said. “It would be kind of a familiar feeling to start the season in Ontario. Obviously that’s not what I want. I want to start the season here and be here for the whole year. But I’ve kind of been through it all now. It’s not all new.” Gravel, isn’t skilled on the offensive end in the mold of an Alec Martinez and despite good size at 6-foot-4, 212 pounds, isn’t a physical presence the likes of MacDermid.