CHICAGO — The good vibes and optimism that the Cardinals carried with them to Chicago didn’t make it through the four-day foray into the Windy City.

Cardinals starting pitcher Jordan Montgomery allowed seven runs in the first three innings as the Cardinals lost their third in a row, 7-2, to the Chicago Cubs in the finale of their four-game series at Wrigley Field.

The Cardinals (44-56) came into the series with an opportunity to gain ground on the Cubs, who are currently in third place in the NL Central, and they appeared poised to do so after a win in the series opener. Instead, the three straight losses in head-to-head games have dropped the Cardinals to 4 1/2 games behind the Cubs (48-51).

The Cubs scored the game’s first seven runs, including a five-run third inning.

Montgomery allowed seven runs (five earned) on six hits, including a home run, and two walks in six innings. He struck out four.

Nolan Arenado went 3-for-4 and made multiple awe-inspiring defense gems at third base, while Alec Burleson (2-for-4, run scored) and Dylan Carlson (2-for-4, two RBIs) also had multi-hit games for the Cardinals.

A costly error

The Cubs scored a pair of unearned runs in the first inning due to a fielding error by Montgomery.

With two outs, Montgomery got Ian Happ to hit a bounced softly back up the middle to the third base side of the pitching mound. Montgomery came off the mound in position to field the ball and make a throw to first base. Montgomery moved too quickly and bobbled the ball. By the time he had a secure grip, he didn’t even make a throw to first base.

Happ reached on a bouncer that should have ended the inning.

Cody Bellinger, who entered the day batting .319 with 13 home runs, came to the plate next and mashed a 1-1 sinker that stayed up and over the middle of the plate.

Bellinger’s two-run home run went an estimated 403 feet and came to rest in the basket above the center field wall.

Cubs thrived in the third

Montgomery (6-8) gave up four hits and two walks in the third inning. He faced nine batters in the frame.

He went to a 3-2 count on the first batter of the inning, Patrick Wisdom, before he walked him. Then with one out, Montgomery again went to a full count before he walked Seiya Suzuki.

Ian Happ’s single loaded the bases, and Bellinger hit a sacrifice fly to center field to drive in the Cubs’ third run. Dansby Swanson followed with an RBI single, and back-to-back doubles by Yan Gomes and Trey Mancini continued the parade around the bases.

Gomes’ liner to left-center scored two runs, and then he sprinted home on Mancini’s double down the left field line.

Montgomery had allowed just four earned runs (five runs total) in his previous five starts.

Cardinals’ rally needed another big hit The Cardinals scored just one run against Cubs starting pitcher Jameson Taillon in 5 2/3 innings. They had seven hits and a walk against Taillon (4-6) as well as six strikeouts.

The lone run Taillon allowed came in the sixth inning. He gave up four of his hits in that inning, including a twoout double by Burleson followed by back-to-back singles by Ivan Herrera and Carlson.

Carlson’s single drove in Burleson. With one run scored in the frame and Herrera and Carlson on base, the Cardinals loaded the bases when Taylor Motter drew a walk from relief pitcher Michael Rucker.

However, Paul DeJong grounded into an inning-ending force out.

The Cardinals got just the one run and stranded three men on base. They went 3-for-8 with runners in scoring position in the game.

Herrera starts, Contreras sits

Cardinals starting catcher Willson Contreras experienced right hip tightness while blocking a ball in the dirt during Saturdays’ game. He exited the game after the fifth inning. His status is considered day-to-day.

Rookie Ivan Herrera, who replaced Contreras in Saturday’s game, started at catcher on Sunday.

Cardinals manager Oliver Marmol said Herrera had been slated to make that start prior to Contreras’ hip ailment.