For three-plus seasons, Allen Bradford’s decision to play football at USC looked as if it might have been a major mistake.

He was recruited to play safety, or maybe linebacker … and got shifted to tailback late in the summer of 2006 when the position was hit by a rash of injuries. After spending most of a year getting ready to play safety … and not knowing the offense when he made the move.

And then a year later, USC had 10 tailbacks, Bradford was denied a chance to move back over to defense, and he got lost in the shuffle.

I can remember talking to Bradford, in 2007,  and the then-sophomore conceded he had wondered if he should transfer … but telling me his father said he should stick it out. See it through.

And now, finally, as a redshirt junior just a season-and-a-half from the end of his college eligibility, Allen Bradford has had his breakout game.

The former fifth- or sixth-string tailback, who was always being assured his chance would come … got his chance Saturday against Oregon State. And he ran (and ran) with it, rolling up 147 yards — more than he gained in his first three seasons combined — and scored two touchdowns on just 15 carries as USC defeated Oregon State 42-36.

Bradford, you may have noticed, is a load. He is listed at 5-foot-11, 235 pounds, and he may weigh more. But he still has significant speed, even while he outweighs most linebackers.

Still, he could never get on the field, for three-plus seasons. His freshman season, it was classmate C.J. Gable who got the start in the season-opener. And Bradford also was behind Stafon Johnson. And Emmanuel Moody. And Chauncey Washington. And some other guys I can’t recall at the moment, back when USC was 10-deep at tailback.

Bradford’s sole claim to fame, those first three seasons, was as a “receiving” tailback. He has good hands. Always has. Back at Colton High School, where I first met him, the Yellowjackets threw to him quite often. At USC, if Bradford suddenly jogged onto the field, the Trojans almost certainly were going to throw to him. Unless it was garbage time, and he got a handful of carries behind the second- or third-string O-line.

Moody, the highly-regarded recruit from Texas, didn’t survive past Year 1. He looked around … and bolted to Florida. That was with Joe McKnight heading up the next recruiting class.

Bradford could have left, too. He almost certainly could have found a prominent school that would let him play safety. But he stayed. I still remember his high school coach, Harold Strauss, telling me, “He loves Pete Carroll. I don’t think Allen will leave.”

And now …

C.J. Gable has faded away, perceived to be not quite fast enough to be a breakaway back and not big enough to be a power back.

Stafon Johnson suffered the freakish (and almost fatal) accident in the weight room, and his career may be over.

McKnight, perhaps the coaches’ first choice to be on the field, has what is euphemistically described as “ball security” issues. Meaning he is prone to fumble. Plus, McKnight has yet to meet a pile he could move, which makes him a less-than-ideal between-the-tackles runner. (And, we should note, how many times has he taken it all the way, even when he gets into the open?)

So, finally, Bradford was No. 1 on the depth chart. He finally got a batch of carries behind the first-string line. And made something of those carries. A lot, actually, including a 43-yard touchdown run.

Now that he has shown that he can accelerate out of a hole — as well as blast into it — it seems likely Allen Bradford will be rewarded with more touches. And perhaps he can become the LenDale White to McKnight’s Reggie Bush — the power guy back there with the quarterback, while McKnight is moved all over the field.

I am happy for Allen Bradford. He is one of the last half-dozen college kids out there who I knew fairly well from my time in the Inland Empire. Most of them are gone, now; this is the second football season I have spent overseas, and it is unlikely (verging on impossible) that I will be getting to know any more prep stars.

It’s nice to see Allen Bradford do some damage. He waited a very long time, and he ran the risk of being lost forever in the very deep talent pool that was the tailback position. But he was a team guy, and some things happened, and now he’s out there … and maybe it will work out for him the rest of the way and he can get a shot at playing in the NFL, which has been his goal since he was a kid at Colton.