Johns, a 6-5, 200-pound senior ticketed for the University of Virginia, has converted 51 of 96 throws for 579 yards and four TDs, with four interceptions.
Quakertown enters with a 4-1 overall record and a 1-0 mark in the conference. Central Bucks South comes in at 3-2 and 1-1.
Gravelle's primary targets are wideouts Nick Nagele (seven catches for 126 yards) and Matt Roberts. At running back, Justin Wieder has carried 44 times for 224 yards and six TDs.
Johns spreads the ball among Chris Veal (20 catches for 274 yards), Dan Bechta, Frank Magasich, and Dan Brown. Brown has rushed 60 times for 475 yards and 11 TDs.
On defense, the Panthers yield an average of 15.8 points. The leaders include linebackers Wieder (48 tackles), Nagele (32), and Ryan Coleman (47).
The headliners for a Titans defense allowing 19.8 points a game are tackles Will Bendon (24 stops) and Pat Litzenberger (19), linebacker Jon Mullin (25), and back Steve Veal (35).
Last year, Quakertown outlasted C.B. South, 41-34.
Pick: C.B. South, 34-26.
Last week: 8-2. Overall: 43-16 (.729).
Thursday
Upper Dublin (4-1, 2-0) at Plymouth Whitemarsh (4-1, 2-0), 7 p.m. Look for QB Russhon Phillips and the Colonials to avenge last season's 33-27 loss. Pick: PW, 24-19.
Friday
No. 6 Roman Catholic (3-2, 0-1) vs. No. 7 Father Judge (4-1, 1-0), at Northeast, 7. Can Judge's Matt Smalley, a quick two-way back, return from a left-ankle injury? Pick: Roman, 28-23.
Downingtown West (5-0, 1-0) at West Chester Henderson (4-1, 2-0), 7:15. The Whippets' Zach Barr has rushed for 836 yards and 10 TDs on 79 attempts. Pick: West, 30-24.
Bishop McDevitt (4-1, 1-0) vs. West Catholic (2-3, 0-0), at Widener, 7:30. McDevitt's Keith Young and West's David Williams get to showcase their rushing abilities. Pick: West, 35-7.
Northeast (3-2, 3-1) at Germantown (2-3, 2-1), 7. LaQuille Nesbitt and the banged-up Vikings will take on Will Parks and the upset-minded Bears. Pick: Northeast, 19-14.
Other games
Communications Tech (4-1, 2-1) vs. Bok (5-0, 4-0), at Southern, 3 p.m. Friday. Pick: Bok, 28-12.
Spring-Ford (4-1, 3-0) at Boyertown (2-3, 0-3), 7 p.m. Friday. Pick: Spring-Ford, 45-21.
Perkiomen Valley (4-1, 3-0) at Phoenixville (4-1, 2-1), 7 p.m. Friday. Pick: Perk Valley, 33-21.
St. Joseph's Prep (3-2, 0-1) vs. Archbishop Ryan (3-2, 0-0), at George Washington, 1 p.m. Saturday. Pick: Prep, 28-13.
Academy Park (4-1, 0-0) at Chester (3-2, 0-0), 10:30 a.m. Saturday. Pick: AP, 21-20.
No. 8 Coatesville (4-1, 1-0) at Bishop Shanahan (2-2, 0-2), 1 p.m. Saturday. Pick: Coatesville, 47-21.
Contact staff writer Rick O'Brien at 610-313-8019, robrien@phillynews.com, or @ozoneinq on Twitter. Read his blog, "The O'Zone," at www.philly.com/ozone
