Ravens general manager Ozzie Newsome is in his bargain-basement mode these days.

Over the weekend the Ravens added two new players, which got a lot of fans excited, but neither center Jeremy Zuttah, formerly of the Tampa Bay Buccaneers, nor former St. Louis Rams safety Darian Stewart should make a dramatic difference to the Ravens this season.

It appears that Newsome is filling in some gaps, like finding another backup running back or a rotational defensive lineman, but the major lifting is over until the NFL draft in May.

Oh sure, Zuttah is better than Gino Gradkowski, who started at center last season for the Ravens. But if grades were given out, the Ravens went from a D with Gradkowski to C or C- with Zuttah.

Quarterback Joe Flacco is still having nightmares from being knocked around last season.

It was a good move by the Ravens. They probably thought Cleveland Browns center Alex Mack cost too much to obtain in some type of deal, and there weren't any good centers left in free agency.

They got Zuttah to redo his deal, which is more salary cap-friendly for the Ravens, and they will have some good competition in training camp among Zuttah, Gradkowski and second-year player Ryan Jensen, who missed all of last season because of a foot injury suffered in training camp.

Zuttah, who is entering his seventh season, has experience, starting 76 of 90 career games. He is athletic, durable and versatile enough to also play guard, which is invaluable among offensive linemen. But let's also take a deeper look.

The Buccaneers had one of the worst offenses in the NFL and once Tampa Bay hired Lovie Smith as the new head coach and Jason Licht as general manager they cut tackle Donald Penn and guard Davin Joseph.

Zuttah was probably next, which is why the Ravens got him in exchange for a fifth-round pick in 2015. In theory, a team can survive with a weak center as long as he is flanked by two good guards.

Right now, the Ravens have two in Marshal Yanda and Kelechi Osemele, but they are thinking about moving Osemele from left guard to right tackle if he fully recovers from offseason back surgery. But if Osemele stays at left guard, do the Ravens take a right tackle in the first round like Michigan's Taylor Lewan or Notre Dame's Zack Martin, or do they wait in the second round to take a guard like Stanford's David Yankey or Mississippi State's Gabe Jackson?

It's intriguing because the key for this team is to significantly upgrade the play of the interior of the offensive line, and that hasn't been done yet even with the addition of Zuttah.

Stewart appears to be more of a special teams player and a stopgap replacement when a starter gets injured. At the end of the season Newsome said he wanted a safety who was rangy and could play pass defense.

Stewart isn't that kind of guy, but he does fit Newsome's mantra: right player, right price. In other words, he comes cheap for a year.

Stewart is a hard hitter and aggressive near the line of scrimmage. He is in the mold of second-year player Matt Elam, whom the Ravens plan to start at strong safety next season.

So the Ravens still need a free safety. There are at least three they like: Alabama's Ha Ha Clinton-Dix, Louisville's Calvin Pryor and Northern Illinois' Jimmie Ward. Signing Stewart is a clear signal that Newsome is poring over his roster and trying to fill it out.

He is unlikely to make a big splash again in free agency unless he finds a deal that even he, a man of great patience, can't turn down.

So far in the offseason the Ravens added a new offensive coordinator in Gary Kubiak and a third-down specialist in receiver Steve Smith, and kept their own high-profile free agents in tackle Eugene Monroe, linebacker Daryl Smith and tight end Dennis Pitta.

Now, it's bargain-basement time until the draft.