That awkward fall Greg Childs took toward the end of Saturday night's training camp scrimmage at Blakeslee Stadium in Mankato? It will cost him the season. The Vikings have announced this morning that Childs tore the patella tendons in both his left and right knees on the fall. He is expected to have surgery in the coming days and will be lost for the season.

The Vikings knew Childs was a bit of an injury risk when they drafted him late in the fourth round in April. The gifted receiver out of Arkansas missed the final five-and-a-half games of the 2010 season after tearting the patella tendon in his right knee. He returned to play in every game for the Razorbacks last season. But with the recovery from his injury progressing slowly, Childs totaled only 21 catches for 240 yards without a touchdown as a senior.

The Vikings still rolled the dice, hoping Childs could return to full health and become a big play threat. His size (6-foot-3, 217 pounds) was a plus. So, too was his speed and ability to make tough catches in traffic. Here's what offensive coordinator Bill Musgrave told us about Childs back in May:

"We're counting on the human body healing up. With the significant injury he had, it's usually a 15- to 18-moth recovery process. And he's just getting to that threshold. So we're betting on the come with him."

Yet Childs suffered a calf strain in rookie mini-camp the weekend after the draft and was limited through organized team activities (OTAs) and mini-camp. That left head coach Leslie Frazier and his staff a bit worried as the team arrived in Mankato for training camp.

Here's what we wrote in the middle of last week:

The Vikings' 2012 revival plans will hinge on patience. And that applies to monitoring Childs' growth. Yet Frazier has been straightforward with what he hopes to see.

"You want him to be able to show that he can stay healthy," Frazier said. "That's a big deal, being available."

Ideally, Childs will prove his health is not a worry and that his potential can be realized.

"His size stands out," Frazier said. "To have a big receiver who can run as well as he can and having the catching radius that he has gives you a belief that even when people have decent coverage, because of his size and ability to catch balls in tough spots, he has big-play potential."

Now, after Saturday's devastating setback, Childs will face another physically and emotionally taxing rehabilitation process and an incredibly steep uphill climb to ever play in the NFL. Not only has he reinjured the right knee that gave him so much difficulty. Now he also has a major left knee injury to worry about.

Childs' injury is also a significant blow to the Vikings receiving corps, which will be without Jerome Simpson for the first three games of the regular season as he serves a three-game suspension in connection with his felony drug conviction.

That opens the door for veterans Michael Jenkins or Devin Aromashou to possibly stick around.

If the Vikings plan on keeping the customary five receivers on their 53-man roster, and we assume Simpson, Percy Harvin and rookie Jarius Wright are locks, who will grab those final two spots? In addition to Jenkins and Aromashodu, Stephen Burton seems to have made an impression on the coaching staff. Emmanuel Arceneaux, Kerry Taylor and Bryan Walters are also in the mix.