ALAMEDA — Khalil Mack was a dominant player during his rookie season, but it took a more sophisticated eye to appreciate it.

Expected to be a dominant pass rusher, Mack had only four sacks in 2014. The No. 5 pick was great against the run and affected more plays than the statistics showed, but any praise for his play almost required the additional line of, “he’s good, trust us.”

That’s not the case this year, with Mack tied for fifth in the NFL with nine sacks — the same total as Broncos All-Pro outside linebacker Von Miller, who he will see Sunday in Denver.

“It’s cool to see,” Mack said of his sack total, “but every week you’re grinding to get that win. You want to get that win at the end of the day and I’m a team guy. Whatever happens, happens as far as statistics, but I’m going to go out there and be effective and get those wins.”

Mack’s sack total has picked up considerably with four in the past two games. He had a hand in three sacks in Sunday’s loss to Kansas City, recording one solo takedown and assisting two others.

“Everybody’s on the same page and we’re communicating and it’s working out pretty well,” Mack said of the recent uptick.

Defensive coordinator Ken Norton Jr. said a lot has to do with Mack’s natural growth in his second season and the Raiders making a concerted effort to let him get after the quarterback more.

“Any time you’re in the league, the second year is always going to be better than the first,” Norton said. “Hopefully, the third is always going to be better than the second. We put him in situations to rush more, to impact the quarterback more. We felt like he was an impact player and he does certain things really well, so let’s have him do that more often, and he’s been fantastic.”

Mack is the highlighted player on a defensive front that has gotten younger as the year has gone along following the season-ending pectoral injury to Justin Tuck and the year-long suspension to Aldon Smith.

Mario Edwards Jr. has elevated his game in their absence with a strong rookie season. Versatile enough to rush from the inside or out, Edwards has steadily increased his impact. He had a sack Sunday, his second in the past four games. The Raiders have 14 sacks during that stretch, nearly equaling the 15 sacks they had through the first eight games.

“I just think it’s us finally putting it together and just working together and understanding how the games work or staying in our rush lanes,” Edwards said.

It makes sense that it has taken some time considering the Raiders’ youth up front. Along with Mack, 24, and Edwards, 21, Oakland’s other primary pass rushers in recent weeks are third-year player Benson Mayowa, 24, and second-year man Denico Autry, 25.

Coaches have preached that work on the line is a game of chess, with moves early in the game setting opponents up for different moves down the road, and that takes time to learn.

“A whole game, you’re working on a guy to set up the one thing that’s going to work at the right time,” Mack said.