The Vikings added another proven starter to the mix on their offensive line, setting up what could be a three-way battle at right tackle.

Two days after he left Winter Park without signing a contract, Andre Smith on Thursday morning agreed to terms on a one-year deal with the Vikings worth up to $4.5 million, according to a source. The free-agent tackle broke the news on Twitter.

"Minneapolis here I come," he wrote. "Excited to join the great Vikings organization."

Smith, who started at right tackle only during his Cincinnati Bengals career, will presumably duke it out with Phil Loadholt, who has missed much of the past two seasons because of injuries, and last year's starter, T.J. Clemmings, at that position.

Loadholt agreed last week to a pay cut to avoid being released. But his restructured deal included no new guaranteed money. Smith, meanwhile, got $1 million guaranteed from the Vikings, who have followed through on their pledge to create competition across their offensive line after that group hamstrung their 29th-ranked offense in 2015.

Before agreeing to terms with Smith, the Vikings signed former San Francisco 49ers guard Alex Boone to a four-year, $26.8 million contract with $10 million guaranteed last week.

Once Smith's deal becomes official, the Vikings will be devoting more salary cap space to the offensive line than any other NFL team, according to OverTheCap.com.

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The addition of those two, who have combined to start 132 games in the NFL, along with the potential return to health of Loadholt and center John Sullivan and possibly the addition of one or two linemen in next month's draft, will make this a crowded group.

Smith, Loadholt and Clemmings, who was a rookie in 2015, have all started 16 games in a season. Starting left tackle Matt Kalil is back for at least one more season. The Vikings also have young tackles Carter Bykowski and Austin Shepherd.

Mike Harris, who had played tackle for most of his life before starting every game at right guard last season, might also be considered an option at right tackle. But it seems more likely that he will compete with Brandon Fusco, who struggled in his first season at left guard, for the right to start at right guard. Boone is penciled in at left guard.

Sullivan should be able to participate in offseason workouts after undergoing a pair of back surgeries in 2015. But Joe Berger played pretty well at center in his absence.

In all, nine of the team's 14 linemen on the roster have started at least 16 NFL games.

Smith has made 73 career starts. The 6-4, 335-pound tackle was the sixth overall pick in 2009 and spent his first seven seasons with the Bengals. Vikings coach Mike Zimmer was the defensive coordinator in Cincinnati for five of those seasons.

While Smith played at a high level at times, injuries plagued the 29-year-old. After drafting offensive tackles in the first and second rounds of last year's draft, the Bengals reportedly did not make a serious attempt to re-sign Smith.

After visiting the Vikings on Sunday and Monday, Smith told the Pioneer Press that he next planned to visit the Arizona Cardinals. But it doesn't sound like the Cardinals were aware of that plan. Smith never visited and their general manager, Steve Keim, told a Phoenix radio station Thursday that he wasn't sure his team was ever even interested in Smith.

It is unclear if the Vikings were bidding against any other teams for Smith's services. But Thursday, they got their guy, setting up an intriguing summer showdown.