Right guard was one of those positions that was a desperate need last offseason and wasn't properly addressed. Now they find themselves with a need there once again.

The attempts to fill the spot were made by signing former tackle J'Marcus Webb to a one-year veteran minimum deal and to draft Jon Feliciano in the fourth round. Feliciano wasn't able to win the starting job and Webb started at right guard all season. Webb was at best a serviceable fill in until a better option could be found.

Here are the top free agents the Raiders could target to finally fill the need at guard:

*If you are looking for Kelechi Osemele, he is on the wish list of offensive tackles.

He is very intriguing because he has some value to the Chiefs. He helped transform the offensive line when he started playing guard last season. He can also play tackle. In fact, he can be your backup center, too. The Chiefs initially put him at tackle in 2014 before an injury brought him down so the Chiefs think he has that kind of ability to play on the outside. He's just an overall solid offensive lineman in a day and age where it seems we see fewer and fewer quality linemen. Someone is going to pay him more than the Chiefs are willing to so I predict he is gone. He deserves a good contract after being such a team player over the past few years. - Joel Thorman, Arrowhead Pride

Rodney Hudson came over to the Raiders last season. Allen was drafted a year after Hudson and the two started alongside each other for two seasons, with Allen at left guard and Hudson at center. In 2013, the two helped pave the way for Jamaal Charles being named All Pro with 1287 yards and 12 touchdowns. And up until Charles was injured last season, he averaged 1398 yards per season in two season with Allen as the starting guard and a combined 17 touchdowns.

As Thorman noted, Allen can back up center and tackle as well which make him even more valuable. He is also just 26 years old, making him even younger than Hudson was when the Raiders made him the highest paid center in the NFL last offseason. Gabe Jackson, Rodney Hudson, and Jeff Allen would give the Raiders one of the best young guard trios in the NFL.

Alex Boone has been a key cog on the 49ers offensive line. He entered the league as a tackle, but switched to guard in 2012. He was an undrafted free agent out of Ohio State who went undrafted because of a serious drinking problem. After spending 2009 on the practice squad, he was inactive for all but one game in 2010. He then became the team's "swing tackle" in 2011, backing up both tackle positions. In 2012, he took over as the starting right guard. He moved to left guard in 2015 after the departure of Mike Iupati. Strengths: He has been a strong guard for the 49ers, but when he has filled in for Joe Staley due to injury, he has been as good, and possibly better. My guess is he wants to play tackle somewhere, but either way, you get tremendous versatility with Boone. He's a behemoth of a man, and can have the kind of nasty in-game edge you want in your linemen. The 49ers primarily ran a lot of power, but began a switch to more zone blocking this past year. He was solid enough this year, but I can't say for certain how he might switch to a more regular usage of zone-blocking. Weaknesses: While he has an edge on the field, there are times where I am not quite sure what to make of his attitude. After Jim Harbaugh left, Boone was interviewed in an HBO special and he mentioned how Harbaugh was a hard-ass, and while it worked initially, "after a while, you just want to kick his ass. . . . He just keeps pushing you, and you're like, ‘Dude, we got over the mountain. Stop. Let go.' He kind of wore out his welcome." - Considering the 49ers had lost Super Bowl 47, and lost a pair of NFC title games, that rubbed fans the wrong way to a certain degree. I don't think he's lazy or anything like that, but that has kind of stuck in my mind. - David Fucillo, Niners Nation

Boone's outspoken attitude may be a bit of a concern (just ask Sio Moore). Then again, you have to think if not for that attitude, he would not become available as a free agent. And he certainly isn't the only one in recent time to get annoyed with the goings in in San Francisco.

At 6-7, 330 pounds and just 28 years old, Boone may receive interest as a tackle. There are a lot of question marks with Boone as far as what he is looking for and how willing he would be to move around. He has the versatility the Raiders like, that's for sure. Who knows, maybe the Raiders would see him as a tackle as well. But if not, he has proven to be a very good power offensive lineman.

The guard has been one of the more durable players along the offensive line the past two seasons. Rarely missing time, Foster was a large part of the team's offensive success. He is a great leader, a great communicator within the game and as noted above, extremely durable. The downside to Foster is his lack of mobility. When guards in the NFL are being required more and more to pull and lead block for runners, Foster struggles in this aspect of the game. Great in both run and pass blocking. - Jeff Hartman, Behind the Steel Curtain

If anyone watched the way the Steelers dominated in the run game last season, you know how much work the offensive line was doing. First it was Le'Veon Bell carving up defenses. When he went down in week six, many thought it spelled doom for the running game in Pittsburgh, but then 32-year-old DeAngelo Williams stepped in and they didn't miss a beat. Williams started 10 games and ran for 907 yards (4.5 yards per carry) and 11 touchdowns.

Foster just turned 30 years old, so he has at least a 3-year contract left in him. He attended college at Tennessee - Reggie McKenzie's alma mater - so he has that in his favor as far as the Raiders' potential interest.

Evans is a free agent by virtue of being cut by the Saints. The 32-year-old is a season removed from a 6-year Pro Bowl run. The Saints came to Evans for the second year in a row trying to get him to restructure his deal to save money against the cap. Evans wasn't agreeable this time so they cut him. He was set to make $8.2 million this season, an amount the Raiders could easily afford, but the Saints cannot.

Evans would bring a lot of experience as a 4-time All Pro and Super Bowl champion. And prior to missing five games last season, Evans had missed two games in his first 9 seasons in the NFL. He may not be the first choice for teams looking for a long term solution, but he could be a dominant force on the line for a couple seasons at least.

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