ST. LOUIS -- The Pirates went into the All-Star break with a roar, winning 12 of their final 17 games. They’ve come out of it with a whimper, losing four straight against National League Central rivals.

The Bucs struggled in every phase of the game Monday night during a rain-soaked, 7-0 loss to the Cardinals in the series opener at Busch Stadium. They were outpitched, as Cards starter Miles Mikolas completed his second career shutout. They were outslugged, as Tyler O'Neill led St. Louis' lineup with two homers. And they were outplayed, as the Cardinals put together a clean game while the Pirates made costly mistakes in the field.

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Pittsburgh entered the second half with a chance to vault back into the division race and give general manager Neal Huntington a reason to add to the roster as the July 31 Trade Deadline draws near. The Bucs can still make that happen, but they’ve been outscored 29-10 since the break and have fallen 5 1/2 games behind the first-place Cubs in the NL Central.

Here are four key moments that led to the Pirates' fourth straight loss:

1) Lost in the lights
With Paul Goldschmidt on first and two outs in the first inning, O'Neill ripped a line drive to left field. Corey Dickerson, last year's NL Gold Glove Award winner in left, glided toward the ball and punched his glove as he prepared to make the catch. But the sinking liner seemingly caught Dickerson by surprise, dropping below his glove and bouncing behind him.

“The first one kind of stunk,” Dickerson said. “We were playing him pull side. He hit a line drive, topspin, kind of similar to [how] a lefty would hit a flare but a lot harder. It just stayed in the lights.”

Goldschmidt scored from first, and Dickerson was charged with only his second error since joining the Pirates in February 2018. That lengthened a vexing inning for Joe Musgrove, who allowed a run and threw 36 pitches despite not permitting a hit and striking out three.

“They had really good at-bats. They fouled off some really tough pitches,” Musgrove said. “When guys do that, it puts you, as a starter, in a tough spot. ... It’s just one of those games where I had to grind my way through and try to make things work.”

2) Dickerson's drop
Dickerson's rough night did not end in the first inning. In the third, Goldschmidt came to the plate with Matt Carpenter on first and one out. Goldschmidt launched a fly ball to the wall in left-center, and Dickerson put himself in position to make the play.

Dickerson timed his jump well and reached up for the ball, but it bounced off the heel of his glove and fell in front of him. Carpenter wheeled around to score, putting the Cardinals up by two. The official scorer awarded Goldschmidt an RBI double. After an infield single, Goldschmidt scored on Dexter Fowler's sacrifice fly.

“I should have made that play,” Dickerson said. “I was on the wall, jumped a little bit. It hit in my glove, popped out. I felt bad for Joe, trying to preserve his outing. It’s unfortunate. Should have caught that ball. That’s how it goes sometimes.”

3) RBI double-turned-double play
No sequence better encapsulated Monday's game than the Cardinals capitalizing on Dickerson's drop immediately before Fowler and a baserunning mistake thwarted the Pirates’ scoring chance in the fourth inning.

Bryan Reynolds, who served as one of the night's bright spots offensively with three hits, was on second after a one-out double to right.

Up came Starling Marte, who crushed a line drive to deep right field that could have put the Bucs on the board. Reynolds ran toward third, and third-base coach Joey Cora waved the rookie around ... but Fowler made an excellent running catch to retire Marte.

According to Statcast, Marte's lineout had an exit velocity of 103.2 mph and an expected batting average of .850. With Reynolds already around third, though, the Cardinals had plenty of time to make the relay throw to second base to complete the inning-ending double play.

“There’s really no need to be around third base. There’s one out and you’re at second base, so you work your way down the line,” Pirates manager Clint Hurdle said. “If a catch is made, you can get back and you’re still in scoring position. If the catch isn’t made, all you’ve got to do is take it on it.”

4) Fouled off, then a big fly
The Cardinals made Musgrove work all night, but they did not do any significant damage against him -- especially when you consider the misplays behind him -- until the fifth. Musgrove took the mound having thrown 88 pitches in four innings, and it finally caught up to him with two outs and O'Neill at the plate.

Musgrove fired a first-pitch fastball, his 99th pitch of the night, trying to force it away from the right-handed O’Neill. But the pitch leaked in and toward the middle of the zone, and O’Neill blasted it out to center for a two-run homer that put St. Louis ahead, 5-0.

Musgrove walked the next hitter then exited the game. He threw 104 pitches in 4 2/3 innings, and the Cardinals fouled off 29 of them. It was not all negative, as he struck out seven and recorded 18 swinging strikes, but it was not enough to match Mikolas as he cruised through nine innings on 100 pitches to deal the Bucs their fifth shutout of the season.

“[Mikolas] was good tonight. He was really sharp,” Musgrove said. “He was able to get contact early in counts and keep guys on the ground. His defense made some really good plays behind him. Perfect remedy for a nine-inning start.”