ALAMEDA, Calif. -- Jack Del Rio made a clear statement about the future of his football team Wednesday in the middle of answering a question about the improvement he's seen from the Oakland Raiders defense.

“As we go forward, we’re going to build a dominant defense here,” Del Rio said flatly. “We’ve taken some steps and showed some signs, but that’s something that will happen. It’s just a matter of when.”

Rookie Ben Heeney's forced fumble was part of Sunday's huge defensive effort by the Raiders. AP Photo/Jack Dempsey

It was a strong take by a defensive-minded coach. Del Rio obviously believes in the importance of defense and is on the record about side of the ball being a strength as his tenure with the Raiders continues.

In recent weeks, the unit has come along. Sunday, for the first time this season, the defense willed Oakland to victory in a 15-12 road upset of the Denver Broncos. The Raiders defense, led by Khalil Mack's five sacks, dominated in the second half.

The Raiders’ defensive players said hearing Del Rio talk about future dominance only motivates them.

“We think we can be dominant now,” rookie linebacker Ben Heeney said. “And we just want to get more dominant. We talk about it every day.”

Added Mack: “No doubt. You’re talking about building it, but we’re working on it every day. We’re working on it every day. You see flashes of it, but you want to put it all together week by week. We’re working on it.”