SAN FRANCISCO >> Right tackle Anthony Davis signed a five-year contract extension Friday with the 49ers, further solidifying a young offensive line that made major strides last season for Super Bowl runner-up San Francisco.

The deal is worth more than $37 million, with $17 million guaranteed.

The 23-year-old tackle has started 16 games in each of his first three years. He helped the 49ers win consecutive NFC West titles and reach the Super Bowl last season, a 34-31 loss to Baltimore.

Davis played at Rutgers and was the 11th overall pick of the 2010 draft, the first of two linemen taken in the first round in general manager Trent Baalke’s first draft in charge. Left guard Mike Iupati joined the Niners with the 17th overall pick, and together they have formed a tight-knit unit that has improved tremendously in protecting the quarterback. Iupati also has started every game.

“Anthony is a very hard-working, dedicated and talented young player who has earned the respect of our entire organization,” Baalke said Friday.  “Having already made significant strides early in his career, Anthony is just beginning to realize his full potential. We look forward to watching him achieve even greater results in the years to come.”

Davis, All-Pro Iupati, tackle Joe Staley and guard Alex Boone all are 28 or younger. Jonathan Goodwin is the experienced center.

The extension for Davis puts him under contract through 2019. He got more guaranteed money than Jake Long, the overall top draft choice in 2008 who went from Miami to St. Louis for $16 million guaranteed this offseason.

Davis’ agent, Drew Rosenhaus, has worked on several new deals with 49ers players in recent seasons and was optimistic last fall of getting something done for the offensive lineman.

Rosenhaus worked on running back Frank Gore’s three-year extension before the 2011 season that takes him through 2014. He then negotiated linebacker NaVorro Bowman’s five-year contract extension in November worth $45.25 million, with $25.5 million in guaranteed money.