Then yesterday, after one freewheeling rollout pass that stunned the Eagles, he reversed the momentum of the game and shoved another unexpected loss down the Eagles' throat.
It was Plummer's 11th career fourth-quarter comeback victory and the second this season against the Eagles.
The play that clinched it looked almost freakish. With 1 minute, 9 seconds left in the game, third and 10 at the Eagles' 39-yard line and the Birds ahead, 17-14, Plummer, the hometown former Arizona State star, took the snap in the shotgun formation and rolled right.
He was going to pass. No, he was going to tuck the ball and run. And just about the millisecond the Eagles' secondary took the bait, Plummer whipped it to wide receiver Frank Sanders, who was somehow open between Damon Moore and Brian Dawkins. Sanders, all knees and elbows, snagged it and tumbled out at the Eagles 1-foot line.
With little ado, Plummer punched it through on the next play for the touchdown.
"Yeah, we work on that play in practice," a grinning Plummer said after the game.
When everybody listening laughed, Plummer said the Cardinals really did practice a very similar play. "Actually, I just take the ball and scramble and everybody breaks their routes."
That's exactly what happened. An Eagles defense that had shut down Plummer and the Cardinals most of the day couldn't hold when it mattered most.
"It's a split-second decision," Plummer said. "I wouldn't have made that play earlier in the season, not with my [injured] thumb."
Sanders had a different view of the play. "He [Plummer] told me, 'Frank, I threw that ball away,' " Sanders said. "I said, 'Jake, you couldn't have tried to throw it away; it was so close.' It was just so perfect for everything. He just barely dropped the ball over the safety's head."
Cardinals coach Vince Tobin said he wasn't surprised by the play. "That's what makes Jake Jake," he said. Tobin even said that Sanders had been the primary receiver on the play all along. "Just not on that route," he added, smiling.
For the Eagles, what was hardest to take about the last-minute turn of events is that they had been in Plummer's face all day. At the end of the first quarter, he had completed only three of six passes for 29 yards. He went six for 13 for 49 yards in the second quarter. The third was not much better, good for only seven yards passing.
The docile Cardinals fans had begun hissing and booing, as if they were telling Plummer to get it in gear or get out.
Then, suddenly, Plummer turned it on in the fourth. He hit Mac Cody for 15 yards, Sanders for 9, Sanders again for 9 more, and on and on, until, finally, with third and 3 at the Eagle's four-yard line, he culminated a 16-play, 80-yard drive by hitting wide receiver David Boston for the touchdown to pull the Cardinals within three points of the Eagles, 17-14.
Of course, it was the final drive - eight plays, 69 yards - that hurt the most, demoralized the Eagles once again and gave the Cardinals their fourth consecutive victory.
"Hopefully, we grew up a little bit with this game," Tobin said.
Plummer shook off most of the praise heaped upon him for the win. "Yeah, I threw it, but somebody had to catch it," he said. "Frank made a burst for the ball. It was him or nobody."
"After playing so terribly for enough of the game, I got sick of it. I flipped the switch. Every time Simeon [Rice] came off the field, he looked at me and said, 'Let's go.' Finally, I listened to him."