He didn't speak to reporters after Oklahoma's 50-49 win at West Virginia two weeks ago, but tweeted an apology to fans for his performance.
“I could barely walk; I felt sick,” Jefferson said of his performance in Morgantown, which he called “horrible.”
Many of Jefferson's issues have stemmed from his aggressive nature. On the first play after halftime in Bedlam last weekend, Jefferson bit hard on quarterback Clint Chelf's play-action fake. Jefferson's brief hesitation left him chasing Josh Stewart, who caught Chelf's pass over the middle and raced for a 75-yard touchdown.
“A good DB knows how to forget bad plays,” Jefferson said.
Oklahoma plays its regular-season finale Saturday at TCU. With a win, the Sooners clinch at least a share of the Big 12 championship and stay alive in the hunt for a coveted BCS bowl berth.
TCU quarterback Trevone Boykin has demonstrated an ability to make plays with his feet; such signal callers have given Oklahoma fits of late.
Stoops said Jefferson needs to be patient and more mindful of the other defenders on the field. On Stewart's 75-yard touchdown grab, for example, Jefferson wasn't at all responsible for run defense.
“That's what's so frustrating,” Stoops said. “That's a young, immature mistake, and he's not a young, immature player.”