The first hour is in the books at the 52nd Rolex 24 at Daytona, the opening round of the TUDOR United SportsCar Championship.

Joao Barbosa in the No. 5 Action Express Racing Corvette DP led a group of four prototypes who opted to pit under the first yellow flag, to lead at the one-hour mark.

However, Barbosa was due to serve a drive-through penalty just past the one-hour mark for a pit lane infraction.

That would promote Brendon Hartley, in the No. 78 Starworks Motorsport Dinan Riley DP, to the overall lead. The New Zealander started 64th overall after the car’s qualifying time was disallowed, and he was into the top-10 overall just after 45 minutes.

Other class leaders at the one-hour mark included the No. 93 SRT Viper GTS-R (Jonathan Bomarito driving, GTLM), the No. 7 Starworks ORECA FLM09 (Pierre Kaffer, PC) and the No. 73 Park Place Motorsports Porsche 911 GT America (Kevin Estre, GTD).

As the Park Place car was last to pit in the first pit stop cycle, the No. 58 Snow Racing Porsche 911 GT America driven by Jan Heylen took over the GTD class lead when Estre pitted.

One spin occurred on the first lap, involving PC class polesitter Jon Bennett in the No. 54 CORE autosport entry after contact from another car. After a brief delay, Bennett resumed at the back of the field.

Several cars – the No. 50 Highway to Help Dinan-powered Riley and No. 57 Krohn Racing Ferrari F458 Italia – needed early pit stops and fell a lap behind within the first 10 minutes of the race.

The first yellow flag flew for Charlie Putman, in the No. 46 Fall-Line Motorsports Audi R8 in GTD, after hard contact in Turn 1; Putman emerged from the car under his own power.

It was an unfortunate incident for one of the fastest cars all week, with Putman’s co-driver and 2013 GT class race winner Oliver Jarvis unable even to turn a lap in his defense.

The yellow flew just 10 minutes into the race; at the time, the overall leaders had not yet caught the tail end of the field for lapped traffic.

Nearly 20 cars took the opportunity to pit during the first yellow period, which lasted for a little more than 10 minutes before the restart. Past the one-hour mark, those cars were due to stop again.

Ferrari ascended to the lead of GTD in the hands of Mika Salo in the No. 72 SMP/ESM Racing entry, with the No. 63 Scuderia Corsa Ferrari 458 Italia GT3 also following suit driven by Toni Vilander. Paul Miller Racing’s polesitting No. 48 Audi R8, driven by Christopher Haase, dropped back to third in class.