Smith into a crash collecting Ron Fellows. After medical issues forced Brian Vickers to sit out the end of the 2013 racing season, Sadler was named to drive the No. 55 MWR for the final four Sprint Cup races of 2013. After going winless, he won the 2014 Aaron's 312 after defending Chris Buescher and Regan Smith, It was his first win since 2012 and his first with Gibbs. On October 31, 2014, it was announced Sadler would join Roush Fenway Racing in the No. 1 for 2015,. During the O'Reilly Auto Parts Challenge, Sadler became ill and exited the car during the first caution. He was relieved by Clint Bowyer. Roush Fenway Racing On October 30, 2014, Roush Fenway Racing announced that Sadler would drive the No. 1 car in the Xfinity Series in 2015. This marked Sadler's reunion with former owner and engine builder Doug Yates, and his fourth stint with manufacturer Ford. In that season he got 4 top 5s and 17 top 10s, although he did not get a win that season, and finished 6th in the standings. JR Motorsports On October 2, 2015, Dale Earnhardt Jr. announced that Sadler would drive for JR Motorsports in the Xfinity Series in 2016. This marked the fifth team Sadler has joined since the 2011 season when he competed for Kevin Harvick Inc. His journey has taken him from KHI to Richard Childress Racing (2012), Joe Gibbs Racing (2013–2014), Roush Fenway and now JRM. On January 6, 2016, Sadler's car number was officially revealed as No. 1. Sadler started out his season with a few top tens. Sadler ultimately broke through at the Sparks Energy 300 at Talladega. On the final lap, it looked like Sadler was set to being the runner-up. Sadler battled Joey Logano on the final lap. When Logano blocked, he spun out from contact from Elliott. Elliott dipped below the yellow line to avoid a spinning Joey. Brennan Poole passed Sadler for the lead just as a caution came out. After a 5-minute delay, with both drivers, Poole and Sadler, waiting on the front-stretch for NASCAR's word, NASCAR ultimately determined that Sadler had been ahead at the moment of caution, dropping Poole to third, and elevating Sadler to first place. The finish was a 1–2 finish for JR Motorsports with Sadler winning and teammate Justin Allgaier finishing second. Sadler would return to Victory lane at