ALAMEDA, Calif. (AP) For as many similarities as there are between Jadeveon Clowney and Khalil Mack as the two dominant pass rushers taken in the top five of the 2014 draft, there are the stark differences as well.
Clowney burst onto the scene as the No. 1 overall high school recruit who went on to dominate the high-powered SEC and become the top pick in the draft. Mack's ascension was far slower as the overlooked two-star high school player who was forced to go to low-profile Buffalo, where he developed into an NFL prospect who seems to get better by the week.
While Clowney entered the NFL with far more hype as the No. 1 overall pick in Houston, Mack has been the far more productive pro ever since being drafted fifth by the Oakland Raiders.
He was a first-team All-Pro last year at both linebacker and defensive end, leads the NFL with 26 sacks the past two years and is a leading contender for Defensive Player of the Year.
''The guy's a walking Hall of Famer, the best in the business,'' teammate Bruce Irvin said. ''I'm blessed to be able to suit up with him week in and week out.''
Clowney and Mack will share the big stage Saturday in Houston in the wild-card opener between the Raiders (12-4) and Texans (9-7). With both teams dealing with injuries at quarterback that have forced Oakland rookie Connor Cook into his first career start and previously benched Brock Osweiler back for his first playoff start, the defenses could well decide this game.
Clowney has taken more time to develop into a star with the Texans as injuries limited him to four games as a rookie, his season was cut short last year by another injury that kept him out of the Texans' playoff game and he has delivered only 10 1/2 sacks in 31 career games - fewer than Mack has had in each of the past two seasons.
But Clowney has developed into one of the top run defenders in the league and Oakland coach Jack Del Rio singled him out as the primary reason the Raiders ran for a season-low 30 yards in 20 carries in the first meeting between the two teams.
''You can say he's grown, but you could tell he has that kind of capability,'' Mack said. ''Just watching him last year, he was amazing against the run and came up just shy of all those sacks and all those different things. With time, you can tell that he's been blossoming and he's a hell of a player.''
Clowney's lack of pass-rush production, especially compared to Mack, led some skeptics to question whether the Texans erred in which pass rusher they took first overall even though his 16 tackles for losses on run plays are one off the league lead this season.
For Clowney, it's only served as motivation.
''All the criticism kind of built me up,'' he said. ''It really helped me off the field with pushing and getting better. Just to come back and prove to them that what they were saying was wrong. It kind of helped me.''
Mack followed up last year's breakthrough season when he had 15 sacks, including five in one game in Denver against Osweiler, with perhaps an even better year.
While his sacks were down with only 11, Mack led the NFL with 96 quarterback pressures, according to Pro Football Focus, sealed a pair of victories over Carolina and Buffalo with strip sacks that he recovered and returned an interception against Cam Newton for a touchdown.
He did all that as well as developing into the emotional leader of the defense following Charles Woodson's retirement with his mantra of ''By any means'' becoming a team slogan.
''Khalil is never surprising,'' defensive coordinator Ken Norton Jr. said. ''The kid is amazing. He's fast. He's strong. He's that basketball player that fills out the stat sheet. Everybody just sees the sacks, but he's in meetings early. He's a leader. He's a guy that the young guys can really lean on to teach. He's always improving. He practices hard. He's the player that everyone loves to coach.''
And the player no offense wants to face.
''He's a stud,'' Osweiler said. ''He's one of the best pass rushers this game has to offer, and there are a lot of good ones out there. He's right at the top of the list. What he's able to do is truly special. He's a very strong player, he's a very athletic player, he's fast, he can bull rush you, he can speed rush you, he has a very high motor, he never takes a single play off.''
NOTES: Raiders LT Donald Penn, who has played 160 consecutive games, missed his second straight practice with a knee injury and might not be able to play. RT Menelik Watson would likely take Penn's spot and Austin Howard would replace Watson on the right side. ... S Nate Allen (concussion) also did not practice for Oakland but has not been ruled out of the game.
AP Sports Writer Kristie Rieken in Houston contributed to this report
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