First-year 49ers coach Jim Tomsula would be wise not to contradict the great Joe Montana, which could spell doom for Colin Kaepernick's career in San Francisco.

The ex-49ers quarterback with four Super Bowl rings and Hall of Fame member is endorsing Blaine Gabbert for the quarterback position, according to Sporting News.

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"I think he's done a great job going in under the circumstances, where the team is and how many people they've lost to injuries," Montana said. "Some people would say it's easier because you're losing and there's only upside, but there's still a lot of pressure to perform when you go in. When you make a change like that, you expect the backup to play well."

The 49ers are 2-2 with Gabbert in the starting lineup, 2-6 with Kaepernick, who could make almost $12 million in 2016, according to the San Jose Mercury News, provided he is still on the roster after April 1.

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Gabbert, meanwhile, has a base salary of $1.75 million, so retaining him makes sense for the 2016 roster.

San Francisco still is lacking a reason in keeping Kaepernick on its roster. The 49ers can't say his work ethic is the reason for his continued slide since guiding the club to an appearance in Super Bowl XLVII. The athletic quarterback spent the first 11 weeks of the offseason working with a quarterbacks coach and studying game video with future Hall of Famer Kurt Warner, in hopes of improving his pocket presence and pocket skills.

But any reports of improvement vanished early on in the 2015 season.

"He's definitely someone you need to keep around," Montana said about Gabbert. "He's proved he can not only play at the level to win games, but also in that offense. That's key in proving his worth to the team. I don't know what will happen with Colin or what their plans are with him, but at this point at time, I don't think you let Blaine get away."

That makes letting Kaepernick get away so much easier for the 49ers, who would be deemed wise listening to the great Joe Montana.

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