INDIANAPOLIS -- The NFL combine enters its fourth day at Lucas Oil Stadium in Indianapolis on Friday, and I'm here covering the event from a Cincinnati Bengals' perspective.

This week we've looked at three key areas the Bengals will want to address during this draft process. There are others, and that's why these few days in Indianapolis are so important to helping determine the direction the franchise goes. At the start of each day, we will provide a quick rundown of what to expect as the team starts examining players it wants on its big board heading into the draft.

Here are three things I'll have my eye on during Day 4 of the combine:

1. On-field workouts begin. The always anticipated on-field workouts begin as the offensive linemen, tight ends and specialists train on Lucas Oil Stadium's turf. A day after bench pressing, their 40-yard times will be recorded, and they'll be taken through other speed and agility and position-specific drills. This will be the final stage of combine testing for the three position groups.

2. Time to meet the pass-rushers. Another group of prospects will meet the media Friday as interviews continue. While it's possible the Bengals ultimately decide to use free agency to fix their pass-rushing issues, they still will take a look at the various defensive linemen and linebackers who arrived in Indianapolis on Thursday. Bottom line: they need help getting to the quarterback after last season's abysmal 20-sack showing. Linebackers who can play Sam, Will and nickel roles are the biggest necessities at that level of the defense.

3. Defensive updates. Speaking of the pass rush, it is sure to be among the topics broached by defensive coordinator Paul Guenther, who is expected to meet with Bengals reporters briefly. Also be on the lookout for more updates from him on linebacker Vontaze Burfict's recovery from knee surgery, and his early thoughts on how the cornerback rotations could break down in 2015.

4. Wrapping up a busy Thursday. You'll also want to keep checking back to the Bengals blog throughout the day as we continue wrapping up a busy Thursday. Head coach Marvin Lewis and offensive coordinator Hue Jackson spoke, and there still is plenty from them to get to.