JOLIET, Ill. -- Tyler Reddick continued his slide from the points lead with a mechanical issue in Sunday's eero 400 NASCAR Cup Series race at Chicagoland Speedway.

Reddick finished 10th in the first stage and was inside the top-10 on lap 134 of 267 when he hit something on the track. That punctured his radiator, causing his No. 45 Toyota to leak fluid and bring out the caution. 

Reddick went to the garage and lost 30 laps due to the puncture. The team got him back out on the track. However, just one caution in the final 133 laps, compared to six in the first 134 laps, meant they couldn't make up any points due to attrition.

"It sounds like we ran over a splitter stay or something like that but it just absolutely destroyed the radiator and the oil cooler so that's a real bummer. I felt we were just finally starting to get the handling turned around... and we were just starting to inch away on it. So it was shaping up to be a good night," Reddick said. "It stinks, 36th two weeks in a row."

Reddick finished 36th at Sonoma Raceway a week before due to power steering issues. That gave Denny Hamlin a one-point lead going into Chicagoland Speedway, where he finished eighth and third in the stages and increased his points lead to 11 heading into the final stage.

In the final stage, Hamlin stayed inside the top-five as his team played the strategy game, pitting a few laps after the leaders. Although he hit the wall in the closing laps, ruining his chance at a win, he finished third and extended his points lead to 44 over Reddick at the checkered flag. 

"I thought I was in control early on, even though I wasn't leading. I probably got a little lazy on some restarts and taking for granted I'd go up and get it. Briscoe and Bell got the cars good in the second half of the race, Byron as well. We just lost the balance in Stage Three, got loose. We went long and thought we were going to get there but just pushed too hard and got the wall," Hamlin said.

Next up for the NASCAR Cup Series is EchoPark Speedway Atlanta. Tyler Reddick won in the spring with 67 points while Denny Hamlin finished 13th with 24 points. A similar swing next week could return the points lead to Reddick.

The drivers listed below are either in Chase contention or are within Chase contention: