San Francisco 49ers

Bubble Boys: Which 49ers are on the edge of a roster spot?

SANTA CLARA -- NFL preseason games are weak overall, but the fourth game? It's the the runt of the litter, the one that Homer Zuckerman, axe in hand, ought to take behind the barn. A case in point: the Tolzien-Johnson Affair of 2012.

I've written about this before. You remember the “battle” between Scott Tolzien and Josh Johnson, right?

In the summer of 2012, they were vying for the role of No. 3 quarterback. It was the only roster competition that remained and, judging from the rhetoric from the coaching staff, it was tight. Jim Harbaugh called it a "dead heat."

Luckily, there was the fourth preseason game to decide it. And the game certainly was decisive. Johnson looked like the second coming of Fran Tarkenton,finishing 9-14 for 125 yards and a 132.4 passer rating.

Tolzien, meanwhile, was a dud. He finished 3-8 for 42 yards, tossed an interception and came away with a passer rating, 15.6 rating, even Blaine Gabbert would find troubling.

And yet the next day it was Tolzien who was declared the winner and Johnson who was cut. What happened? The fourth preseason game, that's what. Yes, there are roster battles in the preseason, but 97.9 percent were decided prior to Tuesday's first round of cuts. The main thing that can determine a roster spot at this point is an injury, which is terrible but true and which is why many starters are likely to make only a cameo appearance, if any, in Houston today.

Having said all that, we still don't know exactly what those roster decisions are. And while many of the guys who play the bulk of today's game are destined to be cut, many will wind up on practice squads and some will be snapped up by other teams. With that in mind, the list of bubble players can be found below.

But first, here's a list of players who are eligible for the practice squad. Remember, though, to reach the practice squad, players first must pass through waivers, which allow every other team a chance to put these players on their 53-man roster.

CB Kenneth Acker: He's the leading candidate to be Marcus Cooper-ed should the 49ers cut him. He's made great progress throughout the offseason. There's likely a dual realization among NFL personnel guys about 49ers defensive backs: 1.) Trent Baalke has a knack for finding good ones at the end of the draft. 2.) Ed Donatell does an excellent job of preparing them for the NFL.

T Carter Bykowski: For the purposes of this post, Bykowski represents all the second-string linemen, including Al Netter, Ryan Seymour, Michael Philipp and Dillon Farrell. There are plenty of other teams in need of depth, if not starters, on the line, and there is a league-wide appreciation that Mike Solari does a great job of preparing his guys. Bykowski stands out because he is a true tackle. Some of the others, particularly Philipp and Seymour, can play tackle but they are probably best as interior linemen. Farrell has good potential but must get stronger. That's why he's the safest bet to make it to the 49ers' practice squad.

CB Chris Cook: He's done everything asked of him during the offseason, and, judging from practices and preseason games, he's improved his ball skills, which was his weakness in four years in Minnesota. Still, if the 49ers were choosing which backup veteran cornerback to keep, they might take Perrish Cox. After all, he can play the slot cornerback spot and also can return punts.

DE Demarcus Dobbs: Going for Dobbs – he's consistently been the team's No. 2 option at right defensive end for the last four offseasons and he plays special teams. Going against Dobbs – there are a slough of younger, bigger defensive linemen eager for playing time.

S L.J. McCray: He's shown potential as a safety and could provide immediate help on special teams. The 49ers, however, seem poised to try to get the undrafted rookie on the practice squad.

CB Darryl Morris: The fastest 49er was cut last year at this time, signed to the practice squad and then bumped onto the active roster. Could the 49ers risk that this year? Morris has triple value: as an outside cornerback, as a slot cornerback and as a coverage specialist.

WR Kassim Osgood: He and Bubba Ventrone last season repaired the team's coverage units after they dipped in 2012. The two may be competing for the same spot. Ventrone currently is dealing with a hamstring issue.

OL Adam Snyder: Snyder's chances were helped greatly by Marcus Martin's knee injury. Snyder now becomes the best option at backup center. He also can play any spot, especially the three interior positions, if there is an injury on the offensive line.

S C.J. Spillman: Spillman played more snaps than any other 49er Sunday against the Chargers. He's been an excellent special teams player for San Francisco but never has made an impact at safety despite a combination of size, smarts and hitting ability. Spillman is entering the final year of his contract. Would the 49ers rather have a young player – McCray? – who will be around for three more seasons beyond this one? Ah, these are the questions that try men's souls.

FB Will Tukuafu: He serves a lot of roles, backup fullback, short-yardage fullback, special teams and, in a pinch, defensive lineman. He has become a “trusted agent” for Harbaugh & co. over the years. But would he be available on the street even if the 49ers cut him?

S Ray Ventrone: See Osgood, Kassim (above).

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