SANTA CLARA — Chris Culliver is the 49ers' wild card this season.

The 49ers did not draft a cornerback until the end of the fourth round on Saturday. They took Dontae Johnson, who started more games at safety for North Carolina State last season than he started at cornerback. He's a developmental project.

So, pencil in Culliver as the 49ers' starting left cornerback next season. The 49ers need him to play more than 1,000 snaps and to cover the opponent's No. 1 receiver.

Why would the 49ers freely choose to depend on Culliver? He is a problem. He is the guy who gave up 123 yards and a touchdown in the Super Bowl. He is the guy who made homophobic comments right before the Super Bowl. "I don't do the gay guys," he said. He is the guy who was driving on a suspended license and hit a bicyclist on March 28, and now is charged with misdemeanor hit-and-run and felony possession of brass knuckles. The NFL may or may not suspend him for a few games next season.

Even if the NFL doesn't suspend Culliver, can the 49ers depend on him? What if he gets himself in trouble on a Friday before a game? How could the 49ers replace the No. 1 cornerback in their game plan two days before they play? The 49ers are at Culliver's mercy.

Let's give Culliver the benefit of the doubt and say he never gets in trouble off the field again. He still wouldn't be dependable.

He tore his left ACL in a non-contact, half-speed special teams drill during last year's training camp. He made a simple cut and his knee gave out. He did not play at all last season.

General manager Trent Baalke says he is not concerned about Culliver's knee. "A lot of players have come back from ACLs. It was a clean ACL (tear). There was no surface damage to the bones. He was fine. Rehab is going extremely well. We feel really good about where he is at."

What if Culliver's knee does not fully recover? Or, what if it gives out again? Most players can bounce back from ACL tears these days. But some players just can't. Look at Kyle Williams. He tore his left ACL in 2012, was much slower in 2013 and then tore the left ACL again on Nov. 22, 2013. Or look at Darius Flemming. He has torn his left ACL twice in two years as a member of the 49ers.

Let's say Culliver's knee fully recovers. He still wouldn't be reliable.

In 2012 when Culliver was the 49ers' No. 3 cornerback, opposing teams figured out they could beat Culliver deep. Although Culliver is a terrific athlete who can shadow receivers, he can't find the deep pass when it's in the air. So, practically every time a team needed a big play against the 49ers in 2012, they threw at Culliver. From Week 6 on, Culliver allowed 8.9 yards per pass attempt and a 97 passer rating.

The 49ers could have drafted a better cornerback than Culliver. Darqueze Dennard, the 2013 Jim Thorpe Award winner for the best defensive back in college football, got picked by the Bengals with the 24th pick in the first round. The 49ers had the 30th pick, and 10 more picks after that. It would have been easy for the 49ers to trade a couple of those picks to move up a few spots and get Dennard, who has the potential to become an All Pro cornerback.

Instead, the 49ers drafted safety Jimmie Ward in the first round. He will cover slot receivers his rookie season and play about 600 snaps — 400 fewer snaps than an outside cornerback like Dennard. Dennard would have had a much bigger impact than Ward next season for the 49ers

And here is the kicker — covering a slot receiver is tougher than covering an outside receiver. Covering a slot receiver is the toughest assignment on the football field. A slot receiver can use the whole field, cut left or right. An outside receiver cannot use the whole field because he lines up next to the sideline.

Like Culliver, Ward is a wild card.

Can the 49ers win a Super Bowl with two wild cards in their secondary? Here's a better question: Why would the 49ers want to find out?

<i>Grant Cohn writes sports columns and the "Inside the 49ers" blog for the Press Democrat's website. You can reach him at grantcohn@gmail.com.</i>