5 Biggest Surprises of San Francisco 49ers' 2015 Season

San Francisco 49ers center Marcus Martin was supposed to be good.

The Niners drafted Martin in the third round of the 2014 draft ahead of quality players such as Oakland Raiders guard Gabe Jackson, Arizona Cardinals wide receiver John Brown and Indianapolis Colts wide receiver Donte Moncrief.

The Niners were counting on Martin. He was going to be the starting right guard, but the Niners moved him to center when doctors decided starter Daniel Kilgore needed extra time to rehab a broken ankle.

Martin never should have been in the 49ers’ plans to begin with. He isn’t strong enough to play in the NFL, and is one of the worst offensive linemen in the league regardless of position.

Martin is an honorary mention for biggest surprise of the 49ers’ 2015 season. In ascending order, here are the biggest surprises.

5. The Rapid Erosion of Carlos Hyde

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The 49ers thought franchise-leading rusher Frank Gore was wearing down. So they let him walk during free agency and replaced him with second-year running back Carlos Hyde, who is younger, bigger and supposedly more durable than Gore.

Gore definitely is wearing down—he’s averaging a career-low 3.6 yards per carry this season with the Indianapolis Colts. But at least he’s on the field. He hasn’t missed a single game. He’s dependable.

Hyde is not. The former Ohio State Buckeye started breaking down just five games into the season. He suffered a stress fracture in his foot against the New York Giants and played through the injury the next two games. But he hasn’t played since Week 7.

Hyde is a violent running back who seeks out contact. He’ll continue to break down unless he changes his running style. The Niners have to replace him or pair him with another starting-caliber running back.

4. The Emergence of Kenneth Acker

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When the season began, cornerback seemed to be the biggest hole in the 49ers defense.

The Niners lost both starters—Chris Culliver and Perrish Cox—during the offseason, and replaced them with Tramaine Brock, a talented veteran, and Kenneth Acker, a second-year former-sixth-round pick who missed his rookie season with a broken foot.

Acker seemed like a backup during OTAs. But he won a starting job outright during training camp and has steadily improved since then. In fact, he has given up two or fewer catches in six of the Niners' past seven games, according to Pro Football Focus.

Acker should be a starter in the Niners secondary for a long time.

3. The Re-Emergence of NaVorro Bowman

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We didn’t know how good inside linebacker NaVorro Bowman would be after missing a season with a gruesome knee injury.

Bowman certainly isn’t as good as he was before the injury—he used to be one of the best coverage linebackers in the NFL. Now, he’s one of the worst, because he struggles backpedaling, planting and changing directions in the open field. Understandable, given the nature of his injury.

Here’s what’s surprising: Bowman is on pace to make 159 total tackles this season, which would be a career high. He’s having a Pro Bowl-caliber season. What a remarkable competitor.

2. The Fall of Colin Kaepernick

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Sure, the Niners lost one of the best head coaches in football—Jim Harbaugh—plus seven starters on the defense during the offseason. Things still seemed OK in Niners Nation. At least they had their franchise quarterback—Colin Kaepernick.

This season, Kaepernick was supposed to become elite, start carrying his team and start making his teammates better. Instead he, crumbled under the pressure. 

Kaepernick threw just six touchdown passes in eight starts and posted a passer rating of 78.5. His replacement, Blaine Gabbert, has a passer rating of 89.5 despite playing with the same players minus tight end Vernon Davis and running back Carlos Hyde.

Big fall for Kaepernick. Will he even be a starter next season?

1. The Rise of Blaine Gabbert

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When Gabbert became the 49ers' starting quarterback Week 9, most of us probably thought he would fail miserably. Some of us may have thought Gabbert didn’t deserve to be in the league and the Niners were doing him a favor—that's how bad he was for the Jacksonville Jaguars.

Apparently, some of us were wrong.

In four starts, Gabbert has won two games, completed 63.0 percent of his passes and averaged 7.6 yards per pass attempt. His predecessor, Kaepernick, completed 59.0 percent of his passes and averaged only 6.6 yards per pass attempt this season.

All of a sudden, Gabbert’s future seems brighter than Kaepernick’s. What world are we living in?

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