ALAMEDA (AP) — As soon as D.J. Hayden woke up, he flashed back one year to the day he almost died in a practice collision.

Hayden got an encouraging text message from his mother Wednesday morning and he said he just felt blessed to be living after undergoing emergency heart surgery last Nov. 6.

After battling his way back from a near-death experience, Hayden’s growing pains as a rookie cornerback in the NFL for the Oakland Raiders appear like minor impediments rather than shaking his confidence after a rough outing last week against Philadelphia.

“I’m just truly blessed,” he said. “Truly blessed to be living right now. Truly blessed to be in the NFL right now. I’m just truly blessed.”

Hayden collided with a teammate in practice at Houston one year ago, tearing a blood vessel off the back of his heart. He was rushed into immediate surgery for a tear of the inferior vena cava, the large vein that carries blood from the lower half of the body to the heart.

The injury is 95 percent fatal in the field, according to doctors, and is most commonly associated with high-speed motor vehicle accidents.

Hayden didn’t know if he’d ever be able to walk again, much less play football. But he eventually recovered and worked his way back to get drafted 12th overall in April by the Raiders. After a setback in May when he had to undergo surgery to repair an abdominal scar, Hayden was finally cleared for contact midway through training camp and has played all eight games so far this season.

“Nothing in football can compare to what he had to go through and the type of mental toughness that it takes to battle through the injury that he battled through and to be able to come back like he’s been able to come back,” coach Dennis Allen said. “I have no doubt that he will be able to respond, he’ll be able to come back and he’ll perform at a high level. Not a lot of people have gone through the things that he had to go through.”

Hayden has played about two-thirds of Oakland’s defensive snaps as the nickel cornerback and has had an up-and-down campaign so far. He struggled at the start of the season but showed signs of improvement with an interception against San Diego on Oct. 6 and a forced fumble the following game in Kansas City.

But he is coming off a disastrous performance against the Eagles. The rough day started when he stopped in the middle of the end zone as Riley Cooper ran past him to make a 17-yard touchdown catch. On Philadelphia’s next offensive play, Hayden lost his footing a bit to lead to a 63-yard TD pass from Nick Foles to Cooper.

“This past game I gave up two touchdowns and it’s something I’ve got to put past me. I’ve got to keep going on to the next play and getting better,” he said. “It’s about how you respond to it. I could have made both plays, I’ve just got to finish the play. If I’d have finished the play, who knows what the outcome would have been.”