Jimmie Johnson leads the first practice session of the Chase

Earlier in the afternoon, NASCAR cancelled qualifying for Sunday’s Teenage Mutant Ninja Turtles 400 so teams concentrated solely on race set up.

Jimmie Johnson, who is still looking for his first win at the 1.5-mile track nestled in Joliet, Ill., led the initial practice session with a lap of 183.780mph (29.383-sec).

Carl Edwards (183.299mph), Denny Hamlin (182.927mph), Brad Keselowski (182.655mph) and Chase Elliott (182.568mph) rounded out the top five in single-lap runs.

Elliott also completed the most laps of anyone at 48, followed by Hamlin at 44.

Alex Bowman, who is filling in for the sidelined Dale Earnhardt Jr., broke up the Chase contenders with the sixth fastest speed (182.285mph). As he was coming to pit road following the one-hour session, he spun out coming off of Turn 4. Martin Truex Jr. (182.106mph) was seventh quick followed by Kyle Larson (182.045mph), Ryan Blaney (182.045mph) and Kyle Busch, who rolls off first on Sunday since he’s the top seed in the Chase.

Other Chasers included Austin Dillon (11th), Kevin Harvick (12th), Matt Kenseth (13th), Kurt Busch (15th), Joey Logano (17th), Tony Stewart (20th), Jamie McMurray (21st) and Chris Buescher (33rd).

Johnson again led the way in ten-lap averages at 180.909mph, followed by Truex, Dillon, Hamlin, and non-Chaser Paul Menard.

Ty Dillon subbed for Regan Smith in the No. 7 Tommy Baldwin Racing Chevy for Regan Smith, who flew back to North Carolina to await the birth of his second child.

Cla	#	Driver	Manufacturer	Laps	Time	Gap	Interval	Mph
1	48	Jimmie Johnson	Chevrolet	39	29.383			183.780
2	19	Carl Edwards	Toyota	31	29.460	0.077	0.077	183.299
3	11	Denny Hamlin	Toyota	44	29.520	0.137	0.060	182.927
4	2	Brad Keselowski	Ford	33	29.564	0.181	0.044	182.655
5	24	Chase Elliott	Chevrolet	48	29.578	0.195	0.014	182.568
6	88	Alex Bowman	Chevrolet	34	29.624	0.241	0.046	182.285
7	78	Martin Truex Jr.	Toyota	35	29.653	0.270	0.029	182.106
8	42	Kyle Larson	Chevrolet	31	29.663	0.280	0.010	182.045
9	21	Ryan Blaney	Ford	29	29.663	0.280	0.000	182.045
10	18	Kyle Busch	Toyota	13	29.672	0.289	0.009	181.990