When you're 39 and headed into free agency, as Uehara is, this is not the finishing kick with which you want to end your season.
And while Sox manager John Farrell said he intended to speak with Uehara about possibly taking an extended rest, or even shutting down, for the season's final 22 games, that may not be the easiest conversation to have with someone whose future employment might be at stake.
It also casts at least a shadow of doubt on what Sox general manager Ben Cherington expressed with such certainty just the day before while sitting in the visitors' dugout here, that Uehara was a major piece in the team's plans for 2015.
Cherington described Uehara's recent struggles as a temporary glitch, but what to believe now? The Sox can cite such recent examples as Mariano Rivera, Trevor Hoffman and Billy Wagner as closers who still thrived at 40 and beyond, but don't the Sox at least have to wonder about the expiration date on Uehara's shelf life?
It's hard to imagine that Uehara wants to end his season in this fashion: Covering his face after giving up a tying home run into the second deck by Mark Teixeira, then two batters later walking toward the dugout even before Chase Headley's drive landed deep into the right-field seats to give the New York Yankees a walk-off 5-4 win in Yankee Stadium.
"I'm responsible for everything, it's my fault," Uehara said in a brief conversation with Japanese reporters while still in uniform before bolting to the trainers' room.
Later, he offered a statement, through interpreter C.J. Matsumoto, that "I was completely out of whack. Nothing was working."
Uehara has given up 10 home runs this season after giving up five in 2013, none in the last three months of the regular season, a span of 134 batters. Jose Lobaton of the Rays broke that string with a walk-off winner in Game 3 of the AL Division Series, but for much of this summer Uehara was every bit as dominant as he had been in his history-making 2013.
Oh, there was some shoulder stiffness in April, a two-homer, ninth-inning glitch in a June game in Oakland that the Sox came back to win, and a mention or two of fatigue, beginning in early July.
But there was nothing to presage the stretch that began Aug. 16 in Fenway Park with a ninth-inning home run by Houston's Jason Castro in a 10-7 Red Sox win. That was the first of five appearances in which Uehara has been charged with three losses, three blown saves and a stat line that has turned Koji Time into a warning to take cover: 4 2/3 IP, 14 H, 10 R, 4 HR, 19.29 ERA.
Two nights ago, Uehara entered with a 7-1 lead in the ninth and gave up a leadoff home run to Brian McCann. That one didn't hurt. The one that Teixeira hit 366 feet into the second deck wiped out, with one swing, the 4-3 lead the Sox had built on two home runs by David Ortiz and one by Brock Holt.
Headley's home run was a blast (414 feet according to ESPN Stats & Information), one that had him lifting his fist in triumph as soon as he connected and sending the Sox home in as much shock as a last-place team can muster.
Both home runs came on split-fingered fastballs that elected to remain elevated rather than diving, a clear indication that Uehara lacks the finish on the pitch that is as critical to his success as Rivera's cutter was to his.
Faulty mechanics could be the issue, but not likely. The more obvious candidate is fatigue, the enemy of all pitchers, the instigator of lower arm slots that cause pitches to take divergent paths from where they're intended.
Uehara did not give up a home run leading off the ninth inning once in 2013. He has done so four times this season.
Through Aug. 15 this season, opposing batters were batting .151 (20-for-132) on splitters thrown by Uehara. Since then, they're 9-for-17, a .529 average, with three of those hits home runs.
Farrell, a former pitcher and pitching coach, does not need to be told when a pitcher is tired. The results speak for themselves. Uehara made 73 regular-season appearances in 2013, nearly double the 37 he'd made the year before in Texas, then tacked on 13 more high-leverage appearances in the postseason.
He pitched until the day before Halloween. He is clearly gassed now, a couple of days after Labor Day. He needs to shut it down. But good luck convincing Uehara that his season ended in the Bronx on Thursday night.