Auto racing preview: Busy weekend for NASCAR in Martinsville, NHRA in Las Vegas

MONSTER ENERGY NASCAR CUP SERIES: STP 500 (500 laps, 263 miles), Martinsville (Va.) Speedway.

TV: Sunday, 2 p.m. ET -- Fox Sports 1. Radio: Motor Racing Network/SiriusXM Channel 90.

THIS WEEK: This will be the 137th Cup race held at Martinsville. It also marks the 70th year of racing at the paperclip-sized, 0.526-mile oval, the oldest active racetrack in NASCAR Cup competition. ... Kyle Busch is the defending winner of this race, while Jimmie Johnson won last fall's race there. Johnson is the winningest active driver at Martinsville (eight victories). ... Kyle Larson won last Sunday's race at Fontana, Calif., the second triumph of his Cup career. He also swept the weekend by winning last Saturday's Xfinity race there. ... Larson (243 points) widened his lead in the NASCAR Cup standings with his win at Fontana. Chase Elliott is second (214), followed by Martin Truex Jr. (205), Brad Keselowski (179) and Joey Logano (174).

NASCAR XFINITY SERIES: The series is off this weekend. It returns to action April 8 at Texas Motor Speedway.

THIS WEEK: Kyle Larson won last Saturday's Xfinity Series win at Fontana, his second win at the 2-mile facility and sixth Xfinity win of his career. ... Elliott Sadler remains atop the Xfinity Series points standings (189), followed by William Byron (172), Justin Allgaier (143), Ryan Reed (143) and Darrell Wallace Jr. (140).

NASCAR CAMPING WORLD TRUCK SERIES: Alpha Energy Solutions 250 (250 laps, 131.5 miles), Martinsville (Va.) Speedway.

TV: Saturday, 3 p.m. ET -- Fox. Radio: Motor Racing Network/SiriusXM Channel 90.

THIS WEEK: This is the 37th Truck Series race at Martinsville. Kyle Busch won this race last year and became the first driver in the track's history to win both the Truck and Cup races on the same weekend. Johnny Sauter won last fall's Truck race at Martinsville. ... Christopher Bell won the most recent race at Atlanta four weeks ago, his third career Truck Series win. It was also the first Truck Series win at Atlanta for Kyle Busch Motorsports. ... Points leaders: Bell (93 points), Sauter (86), Ben Rhodes (86), Kaz Grala (78) and Matt Crafton (72).

VERIZON INDYCAR SERIES: The series is off until the Toyota Grand Prix of Long Beach on April 9.

THIS WEEK: A field of 22 cars took part a week ago in a test at Barber Motorsports Park in Birmingham, Alabama. Australian driver Will Power, a two-time Barber race winner and three-time pole sitter, was the fastest during the six-hour test with a best lap of 1 minute, 7.7518 seconds (at 122.211 mph). England's Max Chilton was second fastest at 1:07.7591 (122.198 mph). There were 14 drivers within one-half second of each other. ... The 2017 season began with a big upset, as Sebastien Bourdais, in his first race for Dale Coyne Racing, took the checkered flag in the March 12 Firestone Grand Prix of St. Petersburg. Last season's series champion, Simon Pagenaud, finished second, followed by Scott Dixon. ... Points leaders (after one race): Bourdais (53 points), Pagenaud (41), Scott Dixon (35), Ryan Hunter-Reay (32), Takuma Sato (31).

NATIONAL HOT ROD ASSOCIATION, MELLO YELLO DRAG RACING SERIES: Denso Spark Plugs NHRA Nationals, Friday through Sunday, The Strip at Las Vegas Motor Speedway.

TV: Sunday, 6 p.m. ET, Fox Sports 1.

THIS WEEK: This is the fourth race of the 24-race national event season. ... Defending race winners are Antron Brown (Top Fuel), Alexis DeJoria (Funny Car) and Jason Line (Pro Stock). ... Winners of the most recent race, the Amalie Motor Oil Gatornationals nearly two weeks ago, were: Tony Schumacher (Top Fuel), John Force (Funny Car), Shane Gray (Pro Stock) and Eddie Krawiec (Pro Stock Motorcycle). It was Force's record-extending 148th win and Schumacher's record-extending 83rd career win. While it was the third race of the schedule for Top Fuel, Funny Car and Pro Stock, Gainesville was the first race of the 16-race Pro Stock Motorcycle schedule. ... Points leaders: Top Fuel -- Leah Pritchett (300 points), Schumacher (279), Brown (243), Doug Kalitta (220), Brittany Force (151); Funny Car -- Matt Hagan (308), John Force (238), Ron Capps (235), Tommy Johnson Jr. (209), Courtney Force (177); Pro Stock -- Greg Anderson (319), Line (281), Gray (226), Bo Butner III (198), Jeg Coughlin Jr. (187); Pro Stock Motorcycle -- Krawiec (120), Andrew Hines (97), Joey Gladstone (81), Steve Johnson (74), Jerry Savoie (63).