The Titans quarterback had led his team to a 24-6 halftime lead over the Jets. He missed only three of his 19 passes, covered 130 yards and threw three money balls in the end zone for touchdowns.
It promised to be best game of Locker's three seasons.
"Jake was on fire,'' said Titans tight end Delanie Walker. "He was rockin' and rolling.''
On the first play of the Titans second series after halftime, Locker's world came unglued.
They had taken over at their own 38-yard-line. Locker threw an incomplete pass seconds before the Jets' Muhammad Wilkerson hit him in the chest and Quinton Coples caught him on the left side as he was going down. Jake Locker would not get up.
It appeared to be serious. When they bring a cart out to carry a player off, the concern quickly encompasses the stadium. He was taken to the locker room and quickly transported to Saint Thomas Hospital to have an MRI for what was described as a hip injury.
The Titans hope it is not a partial subluxation, or partial dislocation of the joint. That causes the ball to move in and out of the joint without tearing the capsule surrounding the joint. This is the injury that forced former Raiders running back Bo Jackson and other football players to retire.
"It hurts. We got a win, but it still hurts,'' Walker said. "Jake was the leader of this offense. He controlled this offense and for him to go down, that kinda hurts.''
At the best Locker will miss a number of weeks. At the worst, he'll miss the rest of the season and perhaps beyond. The news cast a pall over the team and its fans.
"He was out there doing great, on target,'' Titans running back Chris Johnson said of Locker. "Any time you have your leader on offense go down like that, it's going to take a lot of people to step up and make up for the player that went down.
"It was a really big shot. We had a lot of momentum, everything going our way and just for the play to happen like that. It just kind of sucked [the momentum] all out of us.''
In war, when a man goes down in battle, the next one steps up and takes his place. The same applies in football.
The spotlight now shines on backup Ryan Fitzpatrick. He has been a starter in this league at Buffalo, but with Locker still learning the nuances of the NFL game, it has limited Fitzpatrick's practice repetitions.
Fitzpatrick knows what he is facing. There is not much time to prepare for the Kansas City Chiefs Sunday.
"That's tough. That's a spot I haven't been in for a little while,'' Fitzpatrick said. "Obviously your mind is with Jake, kind of thinking about him and hoping everything is OK there. Then on the other hand, we've got a game (to play). Today was just go in there and not screw it up.''
Fitzpatricks' academic background would suggest he will be able to handle any cram session needed in preparing for the Chiefs. The Harvard grad had a 1540 on his SAT test and scored a 48, second highest of all those who have taken the Wonderlic test. He has also played against the Chiefs three or four times when he was with Buffalo.
"The reason I was brought here was to help Jake out and be ready for a situation like this if it came up. If he's not in there, then this is why they brought me here,'' Fitzpatrick said. "No longer to tutor Jake and help him along but to help win football games for this team.''
Locker will remain at Saint Thomas Hospital overnight on Sunday.