In two seasons, D.J. Humphries has gone from perpetually inactive to versatile and essential.
He was drafted by the Arizona Cardinals in the first round out of Florida, the 24th pick overall after leaving school early. And he did not dress for a single game as a rookie.
At first, Humphries was ridiculed by coach Bruce Arians with the nickname ''Knee Deep,'' reflecting how far the coach said his foot needed to be in Humphries' posterior to get the 6-foot-5, 307-pound tackle's attention.
Humphries wasn't offended.
''I think that's just how he works,'' he said. ''I kind of stopped worrying about it. I knew what I had to do on my end for the rest of the year.''
So he went to work.
By late in the season, going against the likes of Dwight Freeney in practice, Humphries had gained a measure of confidence.
''I kind of started smelling myself a little bit,'' he said. ''I knew for sure I could play in this league, as good as our defense is.''
By the end of last season, Arians said he would have no qualms inserting the rookie into the lineup.
''He worked hard,'' Arians said. ''It was just a growth and maturation process, and just maturing as an individual. He was so young, and this is a grown man sport. Those young guys that have had all that success, never failed, and now all of a sudden they're failing and they don't know how to handle it.''
His days of being on the Sunday inactive list were over. Right tackle Bobby Massie left for free agency and the job went to a far more mature Humphries.
He had always played left tackle, though, so the switch required some adjustment.
''It was just like trying to go out and write with your left hand,'' Humphries said, ''because the first-year minicamp was the first time of my playing right tackle. Making that switch, I had to mentally tell myself I could do this.''
Humphries played good enough at the start of the season and steadily improved. Run blocking was his strength - ''a great run blocker,'' running back David Johnson said -, and he was getting better against the pass rush.
Then left tackle Jared Veldheer, the anchor of the offensive line, went down with torn triceps against Carolina on Oct. 30. Little-used John Wetzel started there the next two games. Two weeks ago at Atlanta, the job went to Humphries.
He was going back to his natural position.
''I was actually a little nervous, to be honest,'' he said, ''because I had kind of got settled in at right tackle.''
But it a smooth transition.
''It's pretty clear that's what was natural for me, what I've always played,'' Humphries said. ''I really didn't expect the mechanics to come back as fast as they did, so now I can actually work on fine-tuning the technique, kind of how I was fine tuning on the right tackle side.''
Quarterback Carson Palmer has had a close view of Humphries' development and his switch from right tackle to left.
''He's obviously gifted,'' Palmer said. ''There aren't many guys that can make that transition so seamless, especially being a young guy. It is not like he is in year nine and the first three to four years he played on the right side and then he transitioned to left. To do it in week 13 like he did was pretty special.''
Arians now says the team has ''two left tackles.''
''A great problem to have,'' Humphries said.
He may be Arizona's left tackle of the future. Next season, though, barring some major personnel move, Veldheer will be back in his old spot.
''I think it's pretty clear that I love left tackle. That's all I've ever played,'' Humphries said. ''But I'm willing to do whatever. If next year I'm back at right tackle, I'll be a right tackle playing my butt off again.''
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