KANSAS CITY, Mo. (AP) — The Chiefs didn’t make a first-round selection in this year’s NFL draft. That hasn’t stopped their rookies from making a major impact. Whether it’s been defensive tackle Chris Jones, their first pick who was taken in the second round, or cornerback D.J. White, taken in the sixth round but suddenly playing as many snaps as anybody on defense, those newcomers are a big reason why Kansas City is off to a 4-2 start.

“It’s hard to gauge rookies on what they might contribute,” said Chiefs quarterback Alex Smith, a former No. 1 overall pick. “You get the full spectrum. It’s different for everyone and every position.” Still, the Chiefs picked a bevy of guys who have fit in right away, and injuries and poor play have conspired to move them up the depth chart heading into Sunday’s game against the Colts.

Take their new defensive tackle out of Mississippi State. Jones was supposed to learn the ropes behind Dontari Poe, Jaye Howard and Allen Bailey, but a season-ending injury to Bailey changed that plan. Jones wound up starting his first career game in last Sunday’s win over New Orleans , playing 38 snaps and putting pressure on Drew Brees.

“He did a pretty good job against that explosive offense,” Chiefs coach Andy Reid said. If anyone was expected to contribute right away, though, it was the guy taken with the 37th overall pick.