Colorado has faced a challenging schedule lately, with two ranked teams sandwiching a bye week, followed by this weekend's matchup against Oklahoma State, which has been in and out of the national polls all season and has a top-5 offense in college football.

The tough stretch has led to four straight losses, but one analyst believes this week against the Cowboys could be the Buffs' best chance at an upset. ESPN's David Hale labeled the Colorado-Oklahoma State game as one of his "under-the-radar" games.

Here's what Hale said about the matchup and what Colorado would need to do for an upset:

Colorado lost its eighth straight Big 12 game last week to Utah, but they kept it close and Isaac Wilson has given the offense a spark. For Oklahoma State, last week's loss to Houston probably ended any hopes of a long-shot playoff berth. But Drew Mestemaker's strong second half at least offered some encouragement. Still, it's worth noting an ugly split. In 16 wins over the past three years, Mestemaker's stat line: 80.9 Total QBR, 48 total touchdowns and eight turnovers. In five losses: 62.0 Total QBR, 12 total touchdowns and 13 turnovers. - David Hale, ESPN

According to Hale, the key for the Buffs is forcing mistakes from Mestemaker. When he turns the ball over, his teams struggle to win, and more importantly, Mestemaker seems to compound his mistakes by pushing the ball downfield. In Oklahoma State's Week 1 loss to Tulsa, he threw two interceptions and kept trying to push the ball downfield, completing only 29 of 49 passes.

That kind of performance from Mestemaker likely leads to a Colorado win if the offense can add support. In Mestemaker's college career, his teams (Oklahoma State and North Texas) have gone 1-4 in the regular season when he throws more than one interception, with the lone win coming earlier this year against Oregon.

As Deion Sanders said earlier this week, Chris Marve's defense containing Mestemaker starts with pressure. If Colorado's secondary can get a few takeaways, history suggests an upset win could be on the horizon.