After giving up hits to four of the first five hitters he faced, Papelbon walked Donnie Murphy on four pitches to load the bases and then walked Shin-Soo Choo, too, to bring in the game-ending run for the Rangers' second walkoff win in as many nights.
"He was up in the zone," manager Ryne Sandberg said. "He was elevating pitches and they were on top of the fastball."
"I was definitely flying open a little bit, a tick off my delivery," Papelbon said. "I still have to be able to regroup."
A beaten Papelbon sat in front of his locker stall afterward and almost seemed at a loss for words. Dating back to last year - when Papelbon famously said he "didn't come here for this" when the Phillies' season began to break bad - Papelbon has blown eight of his last 24 save chances.
"We've got a lot more games to play," he said. "Obviously it's a disappointment. Kyle pitched well enough, he deserved a win . . . It's a long season. One of the strongest parts of my game is the ability to bounce back."
Prior to the latest struggles of the former dominant closer, Howard and Kendrick set the Phillies up for a victorious exit from Texas. Howard launched his first home run of the season and Kendrick took a shutout into the seventh inning.
Howard struck out in his first and third at-bats against Texas lefthander Robbie Ross. But in between, Howard jumped on a 1-1 slider Ross left over the inner half of the plate and sent it about 410 feet away to a "Welcome Prince" banner beyond the centerfield fence.
Howard's first home run of the season, a two-run shot in the third, increased the Phillies' lead to 3-0. Carlos Ruiz (2-for-2 with a walk, hitting out of the second spot in the lineup) and Chase Utley teamed up to give the Phils a 1-0 lead in the first inning.
Only one player in baseball will earn more than Howard's $25 million salary for the 2014 season. Howard is obviously no longer one of the game's elite players.
But if he's healthy, hitting home runs and driving in runs, the Phillies' coaching staff, management and the fans who show up to South Philly this summer will be satisfied. After three games in what may be his first healthy season in 3 years, Howard is 4-for-13 with seven strikeouts but also a two-run homer, a run-scoring double, a walk and a scalding line drive out in his final at-bat last night.
"He's that guy for us," Sandberg said of Howard's first series. "I like his swings, when he's making contact he's making big things happen."
Kendrick, a first-time free agent after the season, made Howard's homer and the otherwise meager run support stand up in an American League hitters' park against a lineup featuring the likes of Prince Fielder, Adrian Beltre and Choo.
Coming off an uneven 2013 season - Kendrick was arguably the rotation's most consistent starter in the first 6 weeks and its least in the final 6 weeks - Kendrick flirted with disaster in the first inning of his first start of 2014. He allowed back-to-back singles to begin the night and then tripped over a comebacker to the mound.
But Kendrick recovered from the fielding gaffe and somehow escaped the inning unscathed, too. He caught the lead runner - Choo - in a rundown between home and third to get the all-important second out of the inning and stranded the other two runners in scoring position when the inning ended one batter later.
"Second and third, one out and no runs [in the inning]," Sandberg said. "That set the tone and gave us a lift right off the bat."
Kendrick went on to retire seven straight and 12 of the next 14 batters through the fifth inning. Kendrick had a three-hit shutout brewing with one out in the seventh - all singles - before Mitch Moreland ripped a triple to right-center.
Moreland scored two batters later, ending the Phillies' shutout bid, but Kendrick had a 3-1 lead when he walked off the mound after his seventh and final frame. Kendrick's line: seven innings, five hits, one run, four strikeouts and one walk.
If Kendrick has 15 to 20 more starts like last night - and the other half of the starts aren't dreadful - he likely will be in line for a handsome free-agent payday.
Kendrick, who turns 30 in August, has a 4.04 ERA with 266 strikeouts and 104 walks in 418 1/3 innings in 71 starts since the beginning of 2011. Kendrick avoided arbitration with a 1-year, $7.68 million contract 3 months ago, but could triple that this winter.
Dating back to August 2012, when he replaced Joe Blanton and found a permanent place in the rotation, Kendrick has allowed two or fewer earned runs in 24 of his 43 starts.
For Kendrick, unlike Howard, the money will only come if he produces and stays healthy, too. For at least one night, both the pitcher and the slugger showed off their value.
Papelbon, in the third season of a 4-year, $50 million contract, showed off his value, too - or lack thereof.
"We'll see how it goes," Sandberg said of Papelbon's grip on the closer's job. "I thought [on Monday] he kept them off-balance. He just has to get it down in the zone better and elevated for a purpose. He has to get down in the zone - that's what we're preaching as a staff."
On Twitter: @ryanlawrence21