Michael Waltrip Racing announced on Tuesday that David Ragan will drive the No. 55 Toyota for the remainder of the 2015 Sprint Cup Series season, beginning with the May 9 race at Kansas Speedway.
Brian Vickers was to drive the No. 55 car for MWR this year, but open heart surgery in December forced Vickers to miss the first two races of the season. He returned to racing for the March 8 event at Las Vegas, but two weeks later when the series competed in Fontana, California, he was sidelined by recurring blood clots in his lungs.
Vickers is currently taking blood-thinning medication, preventing him from being able to race. No timetable has been set for his return.
Team co-owner Michael Waltrip is scheduled to drive the No. 55 in this weekend's race at Talladega. Brett Moffitt drove it in six races this season. Moffitt finished a career-best eighth at Atlanta on March 1.
Ragan had been driving the No. 34 Ford for Front Row Motorsports, but after the Feb. 22 season-opening Daytona 500, Ragan moved over to Joe Gibbs Racing to substitute for the injured Kyle Busch in the No. 18 Toyota. Busch suffered a fractured right leg and left foot during an accident in the Xfinity Series season-opener at Daytona.