A single race can make all the difference in NASCAR's Chase.
Ask Jimmie Johnson or Kevin Harvick, the two winners in the second round who are already ensured spots in the round of eight.
But nothing is certain for the 10 other drivers who haven't clinched a spot in the next round, which begins after this week's Hellmann's 500 at Talladega Superspeedway.
Last week's Hollywood Casino 400 at Kansas Speedway proved this much _ points can swing upward or downward, and in dramatic fashion.
Including race-winner Harvick, six drivers saw their positions change by at least two points, completing a radical reshuffling of the standings. Here's a look at the biggest shifts:
