Walding was drafted in Round 5 of the 2011 Major League Baseball draft by the Philadelphia Phillies. He signed for a signing bonus of $800,000, plus having the Phillies pay for his future college expenses. In 2012 in Williamsport he batted.233/.326/.308 with one home run and 31 RBIs, and 66 strikeouts in 253 at bats. Entering the 2013 season, Walding was ranked #20 among Phillies prospects by MLB.com. In 2013 in Lakewood he batted.224/.323/.286 with 1 home run, 42 RBIs, and 121 strikeouts in 402 at bats. In 2014, again in Lakewood, he batted.237/.308/.372 with 7 home runs, 55 RBIs, and 116 strikeouts in 371 at bats. In 2015 with Clearwater he batted.233/.318/.315 with 4 home runs, 31 RBIs, and 117 strikeouts in 403 at bats. In 2016 Walding was a mid-season Florida State LeagueAll Star with the Class High-A Clearwater Threshers, an FSL Player of the Week on both April 17 and June 12, a post-season FSL All Star, and an MILB.com Phillies Organization All Star. For the season, he batted.269 and was tied for 8th in the league with a.440 slugging percentage, and tied for 10th in the league with 111 strikeouts in 350 at bats. In 2017 he was a mid-season Eastern League All Star with the Class AA Reading Fightin Phils. In June 2017, Walding was Eastern League Player of the Month and Phillies Minor League Hitter of the Month, as he hit 13 home runs in 25 games. For the season, he was fourth in the Eastern League with 25 home runs as he batted.236, fourth in the league in slugging percentage as well at.516, and sixth in the league in strikeouts with 127. After starting the 2018 season with the Lehigh Valley IronPigs of the Class AAA International League, for whom he was batting.271/.379/.484 with 7 home runs and 54 strikeouts in 155 at bats, Walding was called up to the major leagues on May 30. He was the MiLB.com International League Player of the Month for July. He concluded his season with Lehigh Valley batting.265/.390 /.474 and leading the league with 73 walks, with 70 runs, 19 home runs, and 69 RBIs with 148 strikeouts in 388 at bats. He was named an International League post-season All Star.
Philadelphia Phillies
Walding made his Major League debut on May 30, 2018, against the Los Angeles Dodgers, going hitless in all four at bats with four strikeouts. He was the first Phillies player to earn a Golden Sombrero in his MLB debut, and the 6th position player in MLB history to do so. Walding was sent back down to the minor leagues on June 6. Walding was called back up to the major leagues on June 20, and struck out again in his first plate appearance, making him the first player in the 143 years of Major League Baseball to strike out in all seven of his first seven major league plate appearances. Additionally, he became the only position player in Major League history to come to bat more than four times to start his career with each at bat ending in a strikeout and joined relief pitcherLogan Ondrusek, who is the only other player ever to strike out seven times in their first seven career plate appearances. On September 14, he got his first major league hit when he hit a two-run home run in the bottom of the 8th inning against Bryan Holaday, after an 0-14 streak to begin his career. In 2018, he batted.059/.158/.235 in 17 at bats for the Phillies with a home run, 12 strikeouts, and two RBIs. Walding began the 2019 season with Lehigh Valley but was recalled by the Phillies on April 20, 2019, following injuries to starting infielders Jean Segura and Scott Kingery. In 2019 he batted.206/.351/.369 with 62 walks, 11 home runs, 40 RBIs, and 130 strikeouts in 282 at bats for Lehigh Valley, and struck out in both at bats for the Phillies. On July 30, 2019, Walding was designated for assignment. He became a free agent following the 2019 season.
Toronto Blue Jays
On March 9, 2020, Walding signed a minor league deal with the Toronto Blue Jays.
