KANSAS CITY, Mo. — Watching from left field, Andrew Benintendi started to hope the ball would come his way, even if hit hard. Anything was more preferable than another walk.

But Matt Barnes couldn’t throw a strike and neither could Robby Scott. In a span of 14 pitches, the Kansas City Royals loaded the bases with no outs in the bottom of the eighth inning on Wednesday afternoon.

“Walks will kill you,’’ Benintendi said. “When the other team walks us it happens that way to them. You’re kind of holding your breath.’’

When Benintendi and the rest of the Red Sox finally exhaled, it was in disappointment. Salvador Perez followed the three walks with a grand slam and the Royals beat the Sox, 6-4.

Even that was torturous. Perez fouled off three full-count fastballs before Scott’s ninth pitch was up and over the plate. Perez hammered it to left field for the first slam of his career.

“I don’t know exactly where the pitch was. It was obviously too good,’’ Scott said.

The Red Sox had been 27-0 when leading after seven innings, their eighth-inning options always coming through. Wednesday also was the first time in 23 games the Sox lost when Barnes pitched in the eighth.

“This one kind of stings because that group has been so good, so consistent for the better part of the whole entire season,’’ manager John Farrell said.

Farrell had it set up the way he wanted. Barnes had not pitched since Sunday and Scott’s only work in the series was facing one batter on Monday.

But Barnes walked Jorge Bonifacio and Lorenzo Cain. Scott then walked lefthanded-hitting Eric Hosmer on four pitches, none of them close.

“Got to be better,’’ Scott said. “Coming into that situation, can’t walk him on four straight.’’

There was no thought of using closer Craig Kimbrel in the eighth inning. He already has pitched more than an inning five times this season, matching his total for all of 2016.

The righthander pitched more than an inning three times from May 30 to June 6 and came away with more than the usual soreness. Farrell decided then that extending Kimbrel over the remainder of the season would be rare, not regular.

It certainly wasn’t going to be with Barnes and Scott rested and the Sox leading by two runs.

“No, that wasn’t something we looked to entertain,’’ Farrell said.

Jackie Bradley Jr. doubled to lead off the top of the ninth. But Royals closer Kelvin Herrera set down Josh Rutledge, Christian Vazquez, and pinch hitter Hanley Ramirez from there.

The Sox were 4-4 on their trip, losing two of three against the Royals.

Drew Pomeranz allowed two runs over 6⅓ innings and was in line for the win before the relievers lost the plate. He has a 3.09 earned run average in his last six starts.

“I think it’s just getting where I need to ne, getting work in and feeling more comfortable,’’ Pomeranz said. “It’s still kind of a work in progress, but I’ve cleaned up a lot of things.’’

Trailing, 2-0, the Sox got back-to-back home runs from Benintendi and Xander Bogaerts leading off the fourth inning to tie the game.

Benintendi’s 10th homer was a 454-foot blast into the fountains in right-center off Ian Kennedy.

Two errors contributed greatly to the Sox taking a 4-2 lead in the fifth inning.

Vazquez led off with a single and took off for second when Deven Marrero put a bunt down. The pitcher, Mike Minor, had an easy play at first but flipped the ball over the head of Hosmer.

Vazquez went to third and Marrero to second on the error. Mookie Betts drove in the go-ahead run with a sacrifice fly to center field. Marrero went to third when Benintendi hit a fly ball to center.

The Royals intentionally walked Bogaerts to get to Mitch Moreland and a better matchup.

Bogaerts has eight stolen bases and Minor wanted to keep him at first. But a pickoff throw went wild and Marrero scored.

The Royals actually caught a break when the throw hit first base coach Ruben Amaro Jr. in the right shoulder, knocking him over. But Marrero was down the line far enough to score ahead of the throw.

The Sox had only five hits, but four runs looked like enough.

Pomeranz put two runners on in the seventh inning before Fireball Joe Kelly was able to squeeze out of a bases-loaded jam. He proved to be the most effective reliever of the day.

“Today was a tough one,’’ Benintendi said. “It happened and it’ll probably happen again. That’s baseball.’’

Peter Abraham can be reached at pabraham@globe.com. Follow him on Twitter @PeteAbe.