DETROIT -- Alex Avila had a glow about him during the recent TigerFest at Comerica Park that made those around him smile, too.
Whether the greater cause of his visible joy was pondering becoming a father for the first time or knowing his knees no longer throbbed like bad toothaches was debatable.
What's not debatable is, Detroits catcher has plenty to smile about with so much to anticipate in 2013.
Last season, the knees, particularly the left one, limited him and contributed to a sizable drop-off in offensive production.
Avila said platelet-rich plasma taken from blood out of his arm and re-injected into his left knee has rejuvenated the stiff and aching joint plagued by tendinitis.
There is a night-and-day difference between the knee this offseason and the last one, Avila said. "The PRP injections worked.
"We talked of doing it since the middle of last season, but you need to take five to seven days off after the injections. I did not want to take that kind of time off during the season ... and so the day after the World Series, we did it here (at the Detroit Medical Center).
"My own blood regenerated the healing process. They separated the platelets from the blood and re-injected it. It worked great.
PRP injections have become popular with athletes in recent years. Golfers Tiger Woods and Fred Couples; baseballs Cliff Lee, Alex Rodriguez and Takashi Saito; basketballs Kobe Bryant and Brandon Roy; and footballs Troy Polamalu, Hines Ward and Chris Canty have sworn by its benefits.
I am very, very anxious to get going on the season, Avila said. Once the holidays were over, I went to bed every night thinking about this season.
His eyes twinkled just recalling those thoughts, and he couldn't wait for the pitchers and catchers reporting date of Tuesday in Lakeland, Fla. Avila drove there on Super Bowl Sunday to begin spring training early.
The best time for feeling good at the plate is the first month, Avila said. You get the kinks worked out.
"You get on the batting tee and in the cage every single day, and get your swing (down). Then theres live batting practice against the pitchers and the games. I cant wait.
The Tigers are getting designated hitter Victor Martinez back from a season lost to knee surgery. They also signed some offensive firepower in free-agent right fielder Torii Hunter.
Imagine what might happen if they have the 2011 version of Avila back in the batting order, too.
Avila hit .295 with 19 homers and 82 RBIs in 2011, when he finished 12th in MVP voting and won the Silver Slugger Award. He also started the All-Star Game at catcher for the American League.
He dropped to .243, nine homers and 48 RBIs last season. His physical limitations began one month into the season, and there were only a few brief stretches when his knees felt decent.
I dont like to make excuses if I was healthy enough to be out there, Avila, 26, said. But now I can put that behind me and train in full heath.
Ive had several MRIs, and the knees check out great. Barring an injury, I should be able to catch for a long time.
"I would think about the knee every time I hit. It was like I was holding back. The left knee is my back leg on my swing -- the one I push off on.
Try getting power into your swing when you cant push off. Good luck. Thats why Avilas slugging percentage dropped from a robust .506 to an anemic .384.
But I dont want to talk anymore about my knees once spring training begins, Avila said. Im healthy. Im good. Im good to go.
And Avila and his wife, Kristina, are awaiting the arrival of more than just another baseball season.
We are expecting our first child, a girl, on April 10, Avila said. We are scheduled to begin an 11-day road trip to the West Coast the next day. Good timing.
Avila shook his head and laughed.
We havent settled on a name yet, he said. We cant wait for it, though. I cant wait to be a father.
Once again, his eyes twinkled.