Erin Henderson, the sixth-year veteran slotted as the Vikings' starting middle linebacker, chuckled when approached with the latest possibility that he won't be holding that role when the regular season opens 11 weeks from now.

The latest threat to Henderson's vision: Desmond Bishop.

Released by the Packers on Monday, Bishop was contacted by the Vikings soon after and scheduled for a Wednesday workout at Winter Park. It'll be a behind-the-scenes audition as the team continues plugging through its three-day minicamp.

Henderson's reaction? Consider it part amused, part edgy.

"It's cool," Henderson said after Tuesday's practice. "I hope it goes well for him [and] the Vikings like what they see. [I'd] welcome him with open arms, welcome him to the team. Not really sure what it's about. I'm just employee No. 50, baby. I just come out here and do what they ask me to do on the field."

At present, the Vikings have asked Henderson to take all the reps as their starting middle linebacker through Organized Team Activities and now in minicamp. And following Tuesday's practice, coach Leslie Frazier tried to skillfully veer away from speculation that Bishop's visit could foreshadow a major change.

"I wouldn't read much into our roster when we work guys out," Frazier noted, "because it's something we're always doing."

Frazier also expressed satisfaction over Henderson's recent growth, lauding his movement in pass coverage and his elevated leadership.

"He's shown more command of the defensive huddle than we expected early on," Frazier said. "You can see he has a lot of control, and the guys really respect everything that he's trying to get done."

Still, that won't preclude General Manager Rick Spielman from eyeing upgrade options. And Bishop's sudden availability carries intrigue.

The former Packer missed all of last season after suffering a severe hamstring tear in the preseason opener. But a year earlier, Bishop delivered 115 tackles, five sacks and two forced fumbles in 13 games. On top of that, his intelligence and passion seem to be "Viking fits" in Spielman's championship blueprint.

So now, the Vikings will try to determine whether Bishop's hamstring has healed enough to enable him to be the impact player he was in 2011. They'll also measure his potential initiation into their 4-3 system and assess his price tag with reports indicating the Chiefs and Jaguars also have interest.

Plus, it might not only be the middle linebacker position the Vikings are concerned about. At present, Marvin Mitchell holds the No. 1 role at weakside linebacker, the position Henderson held the past two years. Behind Mitchell, fourth-round pick Gerald Hodges also could push for a starting spot.

And yet if Bishop were added to the equation, the Vikings would have the option of sliding Henderson back into the role he held last year.

Still, that's not a hypothetical Henderson wants to consider.

"I have a chance to play the Mike now," he said. "I don't see why I would let it slip out of my hands or let it go any other way."

That determination is admirable. But even with Henderson's eagerness and hunger, the Vikings continue exploring their options. Bishop's visit and workout will be the next piece to that puzzle.