"He's a standout pitcher in baseball, he's got a cannon for an arm, and he's a very good athlete," St. Clair said.
The Golden Knights, who use a wing-T scheme, have won their games by a combined score of 215-56. Rebounding from a 35-14 loss to Garnet Valley, Unionville has won six straight by a total score of 217-51.
Here is a closer look at Friday's showdown.
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Last year. In Week 4, host Unionville, with 302 rushing yards on 51 carries, earned a 13-7 victory and went on to claim the American Conference crown.
History. Rustin, which won four straight conference titles starting in 2008, leads the head-to-head series, 4-2.
Sparkplug. Terry Loper, a 5-foot-10, 185-pound junior halfback for the Golden Knights, has carried 146 times for 1,137 yards (7.8 average) and 15 scores.
Quotable. Indians coach Pat Clark: "We have to find a way to slow Loper down. He's the focus, but they also have some nice complementary pieces."
Go-to guys. Pechin's top targets are wideouts Chris Koehler (15 catches for 287 yards, 2 TDs) and David Daly (12 for 229, 4) and halfback Garrett Scargill (10 for 267, 3).
Other threats. Loper, who is being recruited by a number of Division I-AA programs, gets support from quarterback Dave Fithian, fullback Michael Pernsley, and receiver Ethan Ridgeway.
Versatile. Scargill, a 5-9, 175-pound senior, has carried 114 times for 587 yards and six scores.
Up front. Rustin's offensive line is anchored by guard Sean Steinmetz (6-1, 220), tackle Ray Bordley (6-6, 300), and tight end Matt Hosking (6-1, 235).
Paving the way. The Indians' offensive line features tackle Mark Caputo (6-2, 290), center Andrew Jones (5-11, 255), guard John McLaughlin (6-1, 225), and tight end Dan McClaskey (6-3, 215).
Mainstays. Rustin's 5-2 defense, which has allowed eight points per game, is spearheaded by linebackers Steinmetz and Eric Dunion, nose guard Jake Lindauer, and cornerback Omar Stewart.
Analysis. This one is a toss-up. But we expect the Golden Knights to control the ball long and well enough to secure a payback win.
Pick. Rustin, 21-14.