Dan Campbell: Miller is still top RB, but Ajayi is 'up-and-coming'

Jay Ajayi hasn't unseated Lamar Miller just yet, but he's playing extremely well. Rich Barnes Getty Images

When the Miami Dolphins selected running back Jay Ajayi in the fifth round of the draft in May, he likely wasn't seen as Lamar Miller's immediate replacement. A preseason injury for the rookie delayed his start in the NFL, but in his first two games as a pro, he's showed a ton of potential.

Over the past two weeks, Ajayi has rushed for 89 yards on just 11 attempts -- giving him an incredible 8.1 yards per carry average. He's had runs of 23 and 24 yards in each game respectively, showing a great burst and ability to break tackles in the open field.

He's provided a spark to the running game, but Dan Campbell won't be making a change at the top of the depth chart just yet.

"Ajayi is a young guy," Campbell said via the Andrew Abramson of the Palm Beach Post. "He's still up-and-coming. He's gotten better, but he still needs a lot of reps and overall from protection to blitz pick-ups, all those different things, to route running. Not that he can't do it, but right now we have a lot of faith in Lamar Miller. But certainly we like the way Jay runs."

It's hard for the coaching staff not to like how Ajayi runs. There's a reason why he was a highly-touted prospect out of Boise State before concerns about his knee arose. He's a talented back who runs extremely hard but can also catch the ball out of the backfield.

Right now, he's a great compliment to Miller. Following the season, though, he could conceivably be his replacement. Miller is set to become a free agent in the offseason, which means the Dolphins may choose to go with Ajayi as their No. 1 back, with him being a younger, cheaper option. For now, they'll team up to give the Dolphins a dynamic duo.