Ryan Blaney leads Saturday's Cup practice at Las Vegas

Blaney topped the charts with an average lap speed of 183.517 mph, which he set in the first few minutes of the Group A session.

However, late in his 31-lap run on the track, Blaney reported a tire issue.

“I kind of felt something start to go wrong. I decided to come in,” he said. “It went flat coming down pit road. Fortunately, we caught it. Now, it’s trying to figure out what the problem is and how to fix it.”

Ross Chastain ended up second-fastest (183.349 mph) and Erik Jones was third (183.342 mph).

A.J. Allmendinger and Austin Cindric rounded out the top-five.

Among the drivers who ran at least 10 consecutive laps, Blaney had the fastest average speed (182.343 mph). Chastain and Almirola were second and third in that category, respectively.

Group B

Chastain led the way in the second 20-minute practice session with an average lap speed of 183.349 mph.

Allmendinger was second (182.982 mph) and Cindric was third (182.883 mph).

Aric Almirola and Chase Briscoe rounded out the top-five.

There were no on-track incidents in the second session.

Group A

Blaney led the way in the first 20-minute session with an average lap speed of 183.517 mph.

Jones ended up second-fastest (183.342 mph) and Daniel Suarez was third (182.173 mph).

“I was definitely quick there to start so (the car) is good,” Jones said. “Probably need a little bit more speed. There at the end the track was changing and rubbering up. We’d love to qualify good. We don’t usually qualify that good. Hoping this is the weekend we can start a little farther up front.”

Joey Logano and Kyle Busch rounded out the top-five.

There were no on-track incidents during the session.

Cla	#	Driver		Manufacturer	Laps	Time	Gap	Interval	Mph
1	12	Ryan Blaney		Ford	31	29.425			183.517
2	1	Ross Chastain		Chevrolet	22	29.452	0.027	0.027	183.349
3	43	Erik Jones		Chevrolet	20	29.453	0.028	0.001	183.343
4	16	A.J. Allmendinger		Chevrolet	20	29.511	0.086	0.058	182.983
5	2	Austin Cindric		Ford	24	29.527	0.102	0.016	182.883
6	10	Aric Almirola		Ford	22	29.594	0.169	0.067	182.469
7	14	Chase Briscoe		Ford	15	29.640	0.215	0.046	182.186
8	99	Daniel Suarez		Chevrolet	25	29.642	0.217	0.002	182.174
9	4	Kevin Harvick		Ford	19	29.659	0.234	0.017	182.070
10	22	Joey Logano		Ford	14	29.679	0.254	0.020	181.947
11	24	William Byron		Chevrolet	23	29.701	0.276	0.022	181.812
12	18	Kyle Busch		Toyota	18	29.711	0.286	0.010	181.751
13	11	Denny Hamlin		Toyota	14	29.722	0.297	0.011	181.684
14	45	Bubba Wallace		Toyota	19	29.724	0.299	0.002	181.671
15	17	Chris Buescher		Ford	22	29.738	0.313	0.014	181.586
16	41	Cole Custer		Ford	17	29.747	0.322	0.009	181.531
17	5	Kyle Larson		Chevrolet	18	29.755	0.330	0.008	181.482
18	31	Justin Haley		Chevrolet	18	29.779	0.354	0.024	181.336
19	9	Chase Elliott		Chevrolet	25	29.784	0.359	0.005	181.305
20	34	Michael McDowell		Ford	22	29.792	0.367	0.008	181.257
21	48	Noah Gragson		Chevrolet	22	29.793	0.368	0.001	181.251
22	8	Tyler Reddick		Chevrolet	21	29.804	0.379	0.011	181.184
23	21	Harrison Burton		Ford	25	29.805	0.380	0.001	181.178
24	38	Todd Gilliland		Ford	22	29.841	0.416	0.036	180.959
25	47	Ricky Stenhouse Jr.		Chevrolet	16	29.960	0.535	0.119	180.240
26	20	Christopher Bell		Toyota	19	29.980	0.555	0.020	180.120
27	6	Brad Keselowski		Ford	16	30.033	0.608	0.053	179.802
28	42	Ty Dillon		Chevrolet	21	30.039	0.614	0.006	179.766
29	19	Martin Truex Jr.		Toyota	18	30.045	0.620	0.006	179.730
30	7	Corey Lajoie		Chevrolet	17	30.045	0.620	0.000	179.730
31	3	Austin Dillon		Chevrolet	19	30.055	0.630	0.010	179.671
32	23	Ty Gibbs		Toyota	26	30.103	0.678	0.048	179.384
33	15	J.J. Yeley		Ford	11	30.156	0.731	0.053	179.069
34	51	Cody Ware		Ford	15	30.286	0.861	0.130	178.300
35	77	Landon Cassill		Chevrolet	21	30.494	1.069	0.208	177.084
36	78	B.J. McLeod		Ford	6	30.775	1.350	0.281	175.467