Baez's pinch-hit single capped a two-run, ninth-inning rally and lifted the Cubs over Philadelphia 3-2 on Tuesday night to stop the Phillies' four-game winning streak.
Baez didn't start for a second straight game because of a jammed right heel, but the 2018 NL MVP runner-up came through immediately off the bench with the game on the line.
"I'm impressed, but not surprised," said Kris Bryant, who had three hits and used his speed to slide home with two runs. "He's been doing stuff like that the last couple of years. Thankfully, he was up there in that situation to win the game like that."
Chicago trailed 2-1 starting the ninth, but Juan Nicasio (0-2) walked Bryant leading off, Anthony Rizzo doubled and, after Willson Contreras hit a shallow flyout, Jason Heyward was intentionally walked.
Bryant scored when Albert Almora Jr. hit a chopper toward first, and Nicasio's underhand toss to catcher J.T. Realmuto was late, a call upheld by a video review. Baez, lined Nicasio's first pitch to right over a drawn-in infield.
Manager Joe Maddon said he was saving Baez for the moment, even if the injured star might not be able to play in the field after batting for second baseman Daniel Descalso. Cubs head athletic trainer had told Maddon at the start of the inning that Baez was getting taped up and would be available to bat.
"If you don't do it, how do you play defense after that? But a lot of time I don't worry about that stuff," Maddon said.
Kyle Ryan (1-1) got two outs for the win.
Nicasio earned his first save by getting the final two outs in the Phillies' 5-4 win in 10 innings on Monday night. Manager Gabe Kapler was forced to go with Nicasio again after Hector Neris tossed an inning on Monday and Seranthony Dominguez pitched two.
"The way he's been throwing the ball, we felt confident he could get the job done," Phillies manager Gabe Kapler said.
Phillies slugger Bryce Harper went 0 for 4, dropping his average to .224, and failed to reach base at Wrigley Field for the first time in 19 games at the iconic ballpark. Jean Segura doubled in the first to extend his hitting streak to 12 games.
Running on the pitch from second base, Bryant raced home to score in the first inning when Contreras grounded to shortstop. Bryant slid home ahead of first baseman Rhys Hoskins' throw.
Cubs starter Jose Quintana allowed two hits in six shutout innings, leaving after 100 pitches. Philadelphia's Zach Eflin settled down after a 32-pitch first inning that included three walks and allowed one run and six hits in six innings.
CUBS CLOSER CONCERNS
Maddon said he's prepared to finish the season without a designated closer, as long as RHP Pedro Strop returns effectively from a strained left hamstring and RHP Carl Edwards Jr. rounds back into his 2018 form. Edwards was charged with Philadelphia's two runs. RHP Brandon Morrow, who had 22 saves last year before getting hurt in July, has started to throw of flat ground.
Phillies: Kapler said RHP Vince Velasquez (right forearm strain) threw an effective side session on Monday and is on track of a bullpen session on Wednesday.
Cubs: Baez (jammed right heel) didn't start for the second game after starting the first 44. Before the game Maddon said Baez's heel was still sore and he will be checked to make sure the injury isn't more significant. Baez was hurt fielding a grounder in the third inning on Sunday and exited in the sixth.
Cubs LHP Cole Hamels (4-0, 3.13) makes his first start against the Philadelphia on Wednesday. The Phillies drafted Hamels and he won 114 games for the Phillies before he was traded to Texas in July 2015. Phillies rookie LHP Cole Irvin (2-0, 2.77) won his first two starts after his recall from Triple-A.
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