Blues fans have every reason to sweat out Erik Johnson’s knee diagnosis. This team needs Johnson to quarterback the power play and become an all-star caliber offensive defenseman this season.

The Blues need to plug in their power play this season. Johnson has the best point shot among the defensemen and he is the best passer as well. So if he is going to miss time this season, that is really going to hurt.

His absence at the start of training camp puts more focus on the following young defensemen:

Alex Pietrangelo: Long term, he is the Offensive Defenseman of the Future. Conventional wisdom says he could use another year of junior hockey and another 10 to 15 pounds of bulk . . . but if Johnson has a serious injury, the Blues might need his skill to start the season. The team can always send him back to the junior ranks if he can’t hold up against big-boy fore-checking.

Steve Wagner: Before getting demoted to Peoria, he was one of the most reliable outlet passes on the Blues defense. He had eight points in 24 games for the Note last season and 12 points in 23 games at Peoria. He got hurt in the AHL, which set back his development. He doesn’t possess a huge slap shot for the power play, but he could grow into playmaking role on the point.

Jonas Junland: He turns 21 this season and he played with adults in Sweden last year, scoring 20 points in 52 games for Linkoping. Expect him to play in the NHL this season. But will he need significant time at Peoria to adapt to North American hockey?

Roman Polak: He is strictly a defensive defenseman, but he should every chance to break camp with the Blues this season. Like Wagner, he lost a chunk of last season due to injury. Like Wagner, he could have easily stayed with the Blues all last season as assorted veterans faltered. This should be his time to shine.

T.J. Fast: What a great name for an offensive defenseman? The kid looked pretty slick at the prospects tourney, but he will have to learn the defensive side of the game. It will be fun to if he progresses at Peoria this season.

As for the forwards, we’re all eager to see what T.J. Oshie and Patrik Berglund can do. But grinder Chris Porter could make a case for himself and forwards Nicholas Drazenovic and Nikolai Lemtyugov could position themselves for recalls at some point this season.

Both finished last season well at Peoria and both have the skill this team so desperate needs.

AROUND THE RINKS: Scratch Hurricanes forward Justin Williams from your fantasy draft list. He will miss a chunk of the season after suffering an Achilles tendon tear . . . Sergei Zubov will miss the start of the season after undergoing relatively minor hip surgery . . . The peerless Eklund at HockeyBuzz spanked the Blues (gently) for not claiming Mathieu Schneider on waivers. Anaheim ran him through as part its ongoing need to get under the salary cap. The Blues could use a power play quarterback, especially with Johnson’s knee injury clouding that position . . . Would somebody take Nikolai Khabulin off Chicago’s hands and get the Blackhawks in better cap shape? Maybe. Hockey Guy figures LA could use him, but HockeyBuzz insists that Ottawa needs him to take another Cup run. Can’t argue with that – the Sens have mediocre goaltending these days.