So, for inspiration, Parker came up with the slogan "Touch the Line" and worked the Trojans extra hard in practice all week.
It apparently worked to perfection Thursday night as USC outhustled and outlasted the Cougars, 85-76, before 2,622 at the Sports Arena.
"We didn't want to fall short like we had in several games this season, so we wanted to try as hard as we could for as long as we could," said Lorenzo Orr, who led the Trojans with 24 points and eight rebounds. "We know that we have a well-rounded team that just needs to play hard all of the time."
Washington State (6-4, 2-1 in the Pac-10) began the game tied for first place in the conference but could never consistently shake the Trojans' defense, which forced 22 turnovers.
Spearheaded by five steals from Stais Boseman, USC (6-7, 1-2) was able to slow down the Cougars' high-scoring backcourt of Donminic Ellison, Shamon Antrum and Isaac Fontaine, who arrived averaging a combined 44 points a game.
"We knew that it'd be a battle of guards and the key was to stop their (backcourt)," said Parker. "Stais is the focus of our defense. We had to start there, by controlling Fontaine."
The Trojans did not completely stymie Antrum, who finished with 21, or Fontaine, who scored 15, but they did hold Ellison to two points and force the trio into a combined 13 turnovers.
"Our theme this week was to play together and "Touch the Lines,"' Parker said. "We wanted them to reach down within themselves and go all the way to the end, compete the tasks at hand, not just for 30 minutes but for 40 minutes."
In playing its first home game in 23 days, USC started fast against the Cougars, who swept nationally ranked California and Stanford at home last week, in taking a 39-27 halftime lead.
With freshman Cameron Murray breaking out of his three-game shooting slump to make all three of his perimeter shots, Burt Harris adding two three-pointers, and Brandon Martin providing a huge lift off the bench with six points on three-of-four shooting, the Trojans shot 51.7% from the field in the half.
At the start of the second half, Washington State outscored the Trojans, 17-6, in the first three minutes to cut USC's lead to 43-41 before the Trojans responded behind Orr and Murray, who finished with 15 points and four steals.
With 12:30 remaining, USC increased its lead to 57-49 on a driving bank shot by Boseman, who finished with 13 points. From there, the Cougars fought back behind Mark Hendrickson, who scored 18 points in the second half.
Hendrickson, who led the Cougars with 26 points and seven rebounds, led a Washington State rally as the Trojans' lead was cut to 73-71 with 4:20 left. Then Orr took over.
In the final three minutes, Orr scored eight points, grabbed three rebounds and recorded the 117th blocked shot of his career to pass Rod Keller as the Trojans all-time leader.
"I really wanted the ball down there in the final minutes," Orr said. "They were allowing the ball to get inside too easy and I felt that either Jaha (Wilson) or I could exploit that."
USC finished with four players in double figures as Wilson added 14 points to go with his team-high nine rebounds. With the victory, the Trojans improved to 51-9 at the Sports Arena since the beginning of the 1991 season. USC will host Washington Saturday at 3 p.m.