The Oakland Raiders completely overhauled the tight end position this offseason by adding veteran free agent Lee Smith, 3rd round draft pick Clive Walford, and undrafted free agent Gabe Holmes, who joined returning veterans Mychal Rivera and Brian Leonhardt.

These five players will be battling it out not only roster spots, but playing time, when the season rolls around. According to Head Coach Jack Del Rio and tight ends coach Bobby Johnson, Walford can do it all – block and catch. By all accounts, his game speed is faster than his timed speed. Rivera has improved year-over-year his first two seasons in the NFL. Leonhardt passes the eyeball test but has limited playing time. Holmes is an unproven commodity. Smith, well, let's just say he's the sledgehammer of the group.

Let's take a look at what each player brings to the table:

Lee Smith | 6'6" | 265 | Marshall | 5th season

Smith comes over from the Buffalo Bills. He has played in 56 league games with 34 starts. Smith has only caught 20 passes for 144 yards and 3 TDs in primarily a blocking role for the Bills. Raiders tight ends coach Bobby Johnson was the assistant offensive line coach for the Bills during Smith's rookie season. Wide receivers coach Rob Moore served in the same capacity with the Bills last season.

Bottom line: Smith is big, plays with a bit of an edge to him and could be a key cog for the running game. He could also make it tough to decide on the number of offensive linemen when it comes to cut down day. The Raiders have used tackles Khalif Barnes and Matt McCants as short-yardage extra tight ends in recent years.

Mychal Rivera | 6'3" | 245 | Tennessee | 3rd season

Rivera increased his production from year one to year two. He went from 38 catches for 407 yards and 4 TDs in 2013, to 58 grabs for 534 yards and 4 TDs in 2014. He has proven to be an athletic pass catcher who has the ability to make acrobatic catches and snag passes in traffic. His best game came against the San Francisco 49ers last year as he hauled in 7 passes for 109 yards and a touchdown in a 24-13 win.

Bottom line: Rivera has good size and speed and has demonstrated spurts of high productivity during his first two seasons. He has high value as a receiving threat.

Clive Walford | 6'4" | 258 | Miami | 3rd round Draft pick

The confident University of Miami product is a self-described dual-threat tight end. Shortly after the selection, Raiders Head Coach Jack Del Rio said that Walford is a complete tight end and that he was drafted to block and catch. NFL Media analyst Mike Mayock says Walford plays faster than he times. During the offseason program, Walford demonstrated the ability to get up the seam and can use his big body to shield defenders. He strikes an imposing figure and seems to have a bit of a chip on his shoulder.

Bottom line: Is Walford the every-down tight end the Raiders have been looking for since Zach Miller left for Seattle? The coaches seem to hope so and from watching him on the practice field, it's hard to disagree.

Brian Leonhardt | 6'5" | 255 | Bemidji State | 2nd season

Leonhardt made the 53-man roster last season after spending 2013 on the Raiders practice squad. He played in 12 games with three starts, and caught 6 passes for 35 yards and a TD. He missed the last four games of the year after suffering a concussion. Another player who passes the eyeball test and just looks like and NFL tight end, Leonhardt notched 112 receptions for 1,431 yards and 15 TDs in a 43-game college career. He has good size and a lunch pail mentality and has contributed on kick coverage teams.

Bottom line: Although Leonhardt was an upgrade over recent Raiders tight ends and found significant playing time after Davis Ausberry suffered another injury, he is going to have to scratch and claw to make the team.

Gabe Holmes | 6'5" | 254 | Purdue | UDFA

Holmes hauled in 65 grabs for 685 yards and 6 TDs in 49 games for the Boilermakers. Tight ends coach Bobby Johnson is high on Holmes and likes what he has shown so far. His NFL.com scouting report says his has excellent pass-catching skills and that he had some injury issues in college.

Bottom line: Holmes is the wild card here. Although undrafted free agents do make NFL squads, Holmes has an uphill battle. He will have to not just "flash" but shine to find a spot.

The Raiders waived Scott Simonson several weeks ago and added WR Kris Durham. Simonson's release may have trimmed the number down, but it probably doesn't make the decision any easier. All five tight ends have good size and are very young. This position is going to come down to a numbers game. Will the Raiders keep two tight ends? Three? Four? Will the running back and fullback positions have an impact on how many tight ends the Raiders keep?

I do know this – this is going to be one of the more interesting and hotly contested position battles of training camp and there are more questions than answers at this point.