The San Francisco 49ers began an overhaul of their cornerback depth chart this offseason, and one rookie might pay dividends sooner rather than later. The 49ers invested a third round pick in Ahkello Witherspoon, with hopes that he would eventually claim a starting job opposite Rashard Robinson.

Witherspoon struggled at times in training camp, with reports suggesting he had a lot of work to do on technique, and his lack of strength being a problem. It is likely he will have his share of struggles if he gets a significant role in 2017, but he is off to a solid start in the preseason. Pro Football Focus tweeted on Wednesday that Witherspoon has allowed 0.38 yards per cover snap through to preseason games.

New 49ers defensive back Ahkello Witherspoon hasn't allowed much in coverage so far pic.twitter.com/FDOo38xgSe — Pro Football Focus (@PFF) August 24, 2017

I checked with Jeff Deeney, who serves as PFF’s 49ers media correspondent, to get a better idea of what to make of that number. Witherspoon has had 37 coverage snaps, and been targeted once in that time. He gave up a 14-yard reception on that one time he was targeted, which is where the 0.38 comes from. That number ranks eighth out of 64 qualifying cornerbacks.

There are several things to consider with this number. The first is the obvious sample size question. The second is the fact that he has been playing with the second team defense. The third is the reasons why he has not been targeted. We don’t know what’s going through the head of the quarterbacks Witherspoon has faced or where his receiver was on their progressions. But we know quarterbacks are not attacking him like we have seen them attack Rashard Robinson.

We can’t draw firm conclusions from this stat, but given his struggles during camp, it would seem to be at least a decent sign about the direction he is moving. Robinson ranked well in this stat last year, and now he finds himself in a starting role. Ideally we’ll see Witherspoon facing more significant competition before the end of the preseason, but either way, arrow up for him for now.