All games at 7:30 p.m. today.
1- Upper St. Clair (10-0) vs. 9-North Allegheny (7-3)
At Baldwin -- If there has been such a thing as an indestructible force in the WPIAL this season, it has been the Upper St. Clair defense, which has held each of its 10 opponents to fewer than 14 points. That will likely pose a problem for the three-time defending WPIAL champion Tigers, who have been inconsistent offensively for much of the season, though they have picked it up their past few games.
4-Woodland Hills (8-2) vs. 5-Seneca Valley (9-1)
At North Allegheny -- The Wolverines, who traditionally come on strong as the season progresses, have not lost since Sept. 7, though they have been largely unchallenged during that span. That will change quickly against a Raiders team led by quarterback T.J. Holl that has not lost since the calendar turned to October.
2-Central Catholic (10-0) vs. 7-Gateway (8-2)
At Fox Chapel -- The Gators may have more talent than any other WPIAL team, but they've been maddeningly inconsistent, a fact evidenced in a 1-2 stretch to end the regular season. Standing in complete contrast have been the Vikings, who are allowing a WPIAL-best 3.7 points per game and have seen their offense churn out points aplenty behind a multi-faceted rushing attack.
3-McKeesport (10-0) vs. 6-Penn-Trafford (7-3)
At Norwin -- McKeesport won the regular season matchup between the two teams -- a 34-14 victory on Sept. 20 -- but since that point, the Warriors have won five of their past six games. No team has come within 13 points of defeating the Tigers this season and none of their past six opponents have come within 22 points of doing so.
➤ Statistically speaking: Upper St. Clair and Central Catholic's defenses are exemplary, but their balanced offenses are equally crucial to their success. The Panthers (four) and Vikings (three) have a combined seven players who rushed for at least 250 yards in the regular season, a group led by Central Catholic's Luigi Lista-Brinza (920 yards).
➤ History lesson: Woodland Hills has made the WPIAL semifinals in three of the past four years. In two of those seasons -- 2010 and 2012 -- it lost at least two of its first five games. The Wolverines dropped their first two games this season.