Round 4, Pick 20: Albert Okwuegbunam, TE, Missouri
This could be a nice find in the fourth round as Okwuebunam might drop because he is not a major receiving tight end. Jesse James and Xavier Grimble will be free agents and so if they are unable to resign both, then they could get a blocking tight end.
Ogwuegbunam lined up as an H-back and a fullback at Missouri and so he could do a lot of things for you in the run blocking department. I also think he is a good route runner and that could develop into something as a pass catcher.
Round 6, Pick 2: Jesse Burkett, C, Stanford
The Steelers could lose Ramon Foster in free agency and so that makes the depth fall on the interior of the Steelers offensive line. Burkett could be a nice center and guard backup in the NFL. He moves well for a center and fits well into a zone running scheme. He also has good awareness as a pass blocker.
The drawback is that he needs to learn to square himself better against the defender. I think this would be a nice find in the later rounds.