Replacing jettisoned inside linebacker Daryl Smith as a starting inside linebacker, Zachary Orr was all over the field in Week 1.

Facing the Buffalo Bills run-first attack, Orr tallied six tackles, five of which were solo. Shareece Wright, who had one of the best games you will ever see from a cornerback in terms of run support, was the only Raven with more tackles. C.J. Mosley had a relatively quiet game with two tackles and couple quarterback hurries, but Orr picked up the slack.

Orr, a third-year player who originally made the team for his special teams coverage ability, flashed speed and instincts that could elevate the entire defense. He was extremely active throughout the game, the energy he displayed helped the Ravens front rediscover their swarming reputation.

On the Bills first drive, Orr set the tone on first down when he leveled LeSean McCoy after a short reception. Then Orr tackled McCoy behind the line of scrimmage on their second drive before pressuring Tyrod Taylor into an incompletion on third down. Orr continued flowing to the ball to bottle up the run and provided tight pass coverage against McCoy on the Bills third straight unsuccessful drive to begin the game.

Although Orr missed a tackle on a Sammy Watkins crossing pattern and stumbled to enable McCoy to pick up a few extra yards on the Bills final drive before halftime, Orr was not responsible for the blown coverage or goal line defense that allowed their lone touchdown. On the Bills first half drive of the second half, Orr continued getting off blocks to limit McCoy’s rushing success and stopped him short of the sticks on 3rd and 1.

Perhaps most impressive was Orr’s contributions to pass coverage in the middle of the field. He consistently found proper depth on his drops into zone coverage and displayed good awareness when the ball was in the air. Always around the ball, Orr’s presence helped to take away the dump-offs and quarterback scrambles than plagued the Ravens on third down last season.

In the fourth quarter, Orr’s quickness impacted the Bills offense. He closed fast on Taylor, forcing a throw away as he rolled out of the pocket, and then chased down Taylor from behind to force him out of bounds after a short gain on another scramble. On the Bills final offensive play, Orr closed out the the game by pressuring Taylor on an interior blitz that earned a holding call and forced a punt. From the first play to the last, Orr served as the heart of the Ravens defense in Week 1.

Zachary Orr was not the only former un-drafted free agent to contribute to the Ravens win. Outside linebacker Albert McClellan was stout against the run and made his presence felt by disrupting several plays in the backfield. And rookie tackle Michael Pierce was heavily involved in the defensive line rotation, accumulating two tackles up front.

Against the shifty combination of Taylor and McCoy, it was going to take a team effort to stop the Bills rushing attack. The defense was up to the challenge. In vintage Ravens fashion, they held they Bills to a total of 65 yards on the ground with an average rush of 2.7 yards.

If Orr can keep up this level of play, releasing Daryl Smith may end up as one of the Ravens best offseason decisions.