PITTSBURGH (AP) Kris Bryant had so much fun rounding the bases that the star rookie felt like he was a kid again.
And why not?
Bryant turned his tiebreaking two-run double into a Little League homer with some heads-up baserunning, and had three hits and three RBIs Monday night to lead the Chicago Cubs to a 5-2 victory over the Pittsburgh Pirates.
Bryant's double off the base of the left-center field fence in the seventh inning snapped a 1-all tie. He advanced to third base on the throw home and raced across the plate when catcher Francisco Cervelli missed the throw for an error.
''That was fun,'' Bryant said with a grin. ''I don't ever remember ever running all around the bases like that before.''
Bryant, who tied the game with an RBI single in the fifth, is 6 for 14 (.429) with four RBIs in four games since his much-anticipated callup from Triple-A Iowa on Friday. He was a spring training sensation, hitting nine home runs in 40 at-bats for the Cubs.
''He's doing a nice job and there's a really nice slow heartbeat going on right now,'' Chicago manager Joe Maddon said. ''He's just out there playing the game really like I thought he would coming out of spring training.''
Bryant could be joined Tuesday on the Cubs by another top prospect, Addison Russell. The shortstop began playing second base in Triple-A Iowa last weekend, a position that has been a problem in the Cubs' lineup.
''You never know where the need is going to be on the major league level,'' Maddon said. ''Being a little bit more proactive regarding prepping (Russell) for a need that might be open here.''
Cubs second basemen were hitting a combined .135 entering Monday. Chicago has already had three players start at the position in the season's first 12 games - Arismendy Alcantara, Jonathan Herrera and Tommy La Stella.
Russell is hitting .318 with one home run, nine RBIs and one stolen base in 11 games for Iowa.
''You think his bat may be ready to play, you have to get him a position to play,'' Maddon said.
Jake Arrieta (2-1) allowed only one run and three hits in seven innings for the win while striking out seven and walking none.
''We've seen their starting pitcher before and we know how good he is,'' Pittsburgh manager Clint Hurdle said. ''Some nights, there really isn't anything you can do but tip your hat to the opposing pitcher. He pitched a great game, so all we can do is go home and come back tomorrow.''
Jorge Soler, another rookie, went 4 for 5 with a one-out double in the seventh that started the go-ahead rally. Anthony Rizzo followed by drawing a walk then Bryant hit his double off Arquimedes Camninero (0-1).
Rizzo and Starlin Castro each had two of the Cubs' 14 hits.
Starling Marte homered for the Pirates, who had their three-game winning streak snapped in the bottom of the ninth inning and Andrew McCutchen had two hits, including an RBI single in the ninth. It was Marte's third home run in four games.
Pirates starter A.J. Burnett allowed one run and eight hits in six innings. He walked two and struck out one.
The start of the game was delayed 28 minutes because of rain.
The game was delayed 23 minutes in the second inning after a female fan behind home plate was hit in the back of the head by a ball off the bat of Castro.
The woman was standing in the first row with her back toward the field when Castro fouled a ball straight back against the protective screen. The ball was hit with such force that it struck the fan.
The injured fan was eventually removed from the seating area on a stretcher. The Pirates said she was conscious and alert when she was taken to a hospital for testing.
Pirates: SS Jordy Mercer sat out with a bruised chest, an injury he sustained Sunday when he was hit by a pitch from Milwaukee RHP Matt Garza. Mercer might be ready to play Tuesday night. The Pirates said Sunday the injury was to Mercer's ribcage but Hurdle said Monday it was to the chest.
Cubs LHP Travis Wood (1-1) will face LHP Francisco Liriano (0-1) on Tuesday night in the second game of the four-game series. Wood is 3-4 with 4.28 ERA in 14 career games, including 13 starts against the Pirates. Liriano is 4-2 against the Cubs with a 2.30 ERA and has allowed more than two runs in just two of his nine starts against them.