"The good thing about having the telemetry is you can see what’s going on and what’s happening, but it wasn’t anything like we had a warning, it happened all at once," said Stewart, who is returning to NASCAR Sprint Cup Series competition for the first time since breaking his leg last August. "Hopefully the (new) motor we put in will be just as good as this one. If this happened getting ready for the race, you’d be a little more concerned. They pay the big check a week from (Sunday)."

Coincidentally, Patrick’s No. 10 GoDaddy Chevrolet blew its engine as reporters were finishing interviews with Stewart in his garage stall with crew members frantically worked on his car in the background.

But as far as Patrick is concerned the timing may have been a blessing in disguise.

"I only had a few hundred yards to go before the start/finish line then I would have shut it off (and ended practice), so I guess I’m glad it happened then — being five seconds away from blowing up — because that would have been tomorrow (if she had come into the garage as planned)."

None of the four Hendrick Motorsports team cars experienced problems during the two practice sessions. Scott Maxim, director of track engine support for Hendrick Motorsports, confirmed that initially it looked like a problem in the back end of both Stewart and Patrick’s engines.

"Across the board, we’re trying to do the best we can for qualifying for those two laps," said Hendrick Motorsports General Manager Doug Duchardt. "As we work through that process, obviously we’ve been pushing the limit and we found the limit there. So we feel like we understand what’s happening. When we get the engines back over and tear them down for NASCAR, I think we’ll be able to confirm what we think is happening.

"The drivers have been consistent. It feels like it’s been something in the bottom end of the engine. So we think we understand what’s happening there, and we’ll take a look at that. But for tonight and for the rest of the week when we go to race, we don’t really have any concerns with The Sprint Unlimited or as we get into the (duel races) or the 500."

SHR driver Kevin Harvick was fastest of any cars using the Hendrick motors — fourth in the second practice. Hendrick driver and defending Daytona 500 winner Jimmie Johnson was ninth quickest.

Patrick’s best lap was 22nd fastest and Stewart was 38th in the final session.

"Sure it was a concern when I saw Tony blow up," Patrick said. "It was like, ‘Man, are we doing something?’ It wasn’t necessarily specific to our team, I guess, but it’s something we’re doing in our family here and we need to figure it out. I bet other Hendrick cars are thinking, ‘What’s going on?’ We’ve got time to hopefully figure out, definitely figure it out before the race."

Despite the mechanical setback, Stewart said he was still feeling good physically after getting extended time behind the wheel. Friday’s two practices for The Sprint Unlimited — an hour and 45 minutes of track time — were Stewart’s first laps since being medically cleared to compete.

"Yesterday was a little more fun, today definitely feels like I’m back to work," Stewart said, mustering a smile. "Single-car runs aren’t very fun for the driver, but they’re necessary. I still feel good and I’ve got all afternoon to rest and get ready for tonight."

Patrick’s veteran crew chief Tony Gibson took the first-day woes in stride.

"These things happen," Gibson said. "You’re asking these engines to do a lot, run a lot of RPMs, run hot, a lot of crazy stuff. Obviously, they’ve proven we can build really fast motors. Those guys will come up with an answer and we’ll put another one in here and we’ll be fine.

"It could just be a batch of something. Engine parts are crazy. You could get a thousand parts and have only two of them with a nick or something like that. I imagine those other guys are really nervous, but they do a fantastic job and we never have engine problems."

Saturday was a far cry from Patrick’s 2013 Daytona Speedweeks, a fact not lost on Gibson or Patrick. At this point last year, she was solidly atop the practice speed charts and went on to make history as the first woman to earn the Daytona 500 pole.

"It’s definitely a departure from last year when we were really quick when we unloaded and were fast each practice and everything was perfect," said Patrick, who led five laps in the Daytona 500 and finished a historic best eighth place. "This is a different year and that happens. That’s why when (the media) asks what I expect for the year, you have to really get into the year to set expectation levels. This is already very different from the last time.

"But I don’t doubt their effort and ability to fix this, so the bright side is it didn’t happen in qualifying, it happened before."

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