Grossman, a free-agent addition who earned the starting left field job in spring training, hit a three-run homer that tied the game at 5-5 in the middle of a nine-run outburst in the fourth inning. An inning later, Miller became the first Rangers player in 11 years to homer in consecutive season openers. His two-run shot made it 11-6.
While deGrom struck out seven without a walk, the two-time National League Cy Young Award winner allowed five runs on six extra-base hits in his 3 2/3 innings. He threw 49 of 73 pitches for strikes. DeGrom signed a $185 million, five-year contract in free agency and made his fourth career start on opening day - he threw 17 scoreless innings in his three openers for the New York Mets, his team for the past nine seasons.
Aaron Nola, the 29-year-old right-hander making his sixth and maybe final opening-day start for the Phillies, also allowed five runs in 3 2/3 innings. Nola is in the final year of his contract and discussions about an extension ended just before the start of the season.
ESPN baseball insider Buster Olney talks Phillies, chances of another World Series run
The game also marked the Rangers debut of Bruce Bochy, the three-time World Series champion who was back in the dugout after a three-year retirement for his 26th opener as a manager. He had previously managed 13 seasons with the San Francisco Giants, who clinched their 2010 title in Texas, and 12 seasons with the San Diego Padres.
The Phillies, who last season made it to their first World Series since 2009, took a 5-0 lead when No. 9 hitter Brandon Marsh, the first batter after deGrom departed, had an RBI single off Cole Ragans (1-0).
Ragans, the second of five Rangers pitchers, got his first big league victory even while also giving up a walk while facing only three batters.
Alec Bohm hit a two-run homer in the second inning on a 99 mph fastball from deGrom. Marsh and Trea Turner, in his first game with the Phillies after signing a a $300 million, 11-year deal in free agency, had back-to-back triples in the third before J.T. Realmuto had an RBI double.
Grossman's homer came immediately after an two-run double by Jonah Heim. The Rangers went ahead 6-5 when, with the bases loaded, Nathaniel Lowe hit a dribbler in front of the plate that turned into an RBI single off reliever Gregory Soto (0-1).
Fans celebrate start of season
It was the first Opening Day on the road for the Phillies since 2018.
Fans gathered at the King of Prussia Town Center Pavilion for a watch party.
"Being out here with all the fans, you know, just having a good time and being with a big screen is great," said Alec Kostival of Reading, Pa.
Preparations for this season began early in South Philadelphia. Bill Tee was one of the first to arrive at the Citizens Bank Park ticket counter Thursday morning.
"I tried to be the first one at the gate for our tickets, for my wife, for her birthday. Great seats," said Tee from South Jersey.
There was a steady flow of customers at the New Era Team Store as fans stocked up on some of the latest swag.
"This is a 12-month jersey. She's been wearing it for two years, so we're like, 'She needs a new jersey,'" said Jessica Pavlow of Mantua, NJ. "We're going to the game next week against the Yankees in New York, too. We can't wait."
According to Stubhub ticket sales, the Phillies are the #5 most in-demand team, moving up from the #9 spot last year.
Opening Day game prices start at $147.
"I have my tickets. As a matter of fact, I bought three different sets: standing room only, 300 level, and on the first base side. So I'm really crazy, I'm very excited," said Diane Quinnwillauer.
Up next
The second game of the series Saturday is a matchup of 2021 All-Star pitchers. RHP Nathan Eovaldi makes his Rangers debut after signing as a free agent. RHP Zach Wheeler is 30-19 with a 2.82 ERA in his 69 starts the last three seasons since joining the Phillies.
When is the Phillies' home opener?
The Phillies will take on the Cincinnati Reds next Thurday, April 6, at Citizens Bank Park. First pitch is set for 3:05 p.m.
New food options
There are some new food options at The Bank, including Greens and Grains, an Atlantic County, New Jersey, vegan-based restaurant.
"It's the first plant-based restaurant to take residency at a Philadelphia sports venue," says Jared Kane, director of development, at Greens and Grains. "We're very humbled by that, and it's one of the only a handful in the entire country. Two, three years ago, I'm not sure this is something we would have would have dreamed about."
New snacks unveiled ahead of opening day at Citizens Bank Park
On the ballpark menu, you'll find two of their best sellers: the gyro pita and the chk'n parm pesto panini.
Other new options this year include Federal Donuts Chicken Tenders, served with an everything rooster dipping sauce (spicy mayo with pickled everything spice).
There's a new Mexican street popcorn tossed on-site with Tajin spice, lime and cotija cheese.
Also, you'll find South Philly disco fries with roast pork, melted sharp provolone cheese, broccoli rabe and roasted red peppers.
Uncle Charlie's Steaks is a whole new area in concessions.