By CBS 2 Chicago Staff

CHICAGO (CBS/AP) — Despite leading the White Sox to their first winning record since 2012 and their first playoff appearance since 2008, manager Rick Renteria and pitching coach Don Cooper won’t be back on the South Side in 2021.

General Manager Rick Hahn announced Monday morning the White Sox “mutually agreed to part ways” with both Renteria and Cooper. The White Sox said decisions on the rest of the coaching staff “will be determined moving forward and in consultation with the team’s next manager.”

“This is obviously not an easy decision for any of the parties involved to come to. You will not hear me – nor, do I suspect, anyone with the organization – to share with you anything negative about Ricky Renteria in terms of factors in this decision,” Hahn said. “Ricky is obviously a fantastic baseball man, and probably a better person than he is a baseball man.”

The White Sox were 236-309 in four seasons under Renteria, but went 35-25 in the pandemic-shortened 2020 season, finishing second in the AL Central, and making their first postseason appearance in 12 years.

Cooper had been the team’s pitching coach since 2002, and was the last remaining holdover on the coaching staff of the 2005 team that won the World Series.

“The front office and White Sox fans owe a debt of gratitude to Don for everything he did over the years,” Hahn said.

The White Sox lost to the Oakland Athletics in the best-of-three wild card round, and Renteria’s handling of the pitching staff in the winner-take-all third game, when he pulled starting pitcher Dane Dunning after only four batters in a scoreless game, only to watch his bullpen plan implode when reliever Garret Crochet exited with an arm injury, and the rest of the pitching staff couldn’t hold a 3-0 lead.

He brought in rookie Matt Foster with the bases loaded in the fourth inning of Game 3 against Oakland, only to watch him walk in the tying and go-ahead runs. The team ended up using nine pitchers in a 6-4 loss.

Renteria also drew criticism through the regular season for his handling of the lineup, including his decision to continue playing Nomar Mazara as their regular right fielder over Adam Engel, despite Mazara posting a slash line of only .228/.295/.294 with only one home run and 15 RBI in 149 plate appearances, compared to Engel’s .295/.333/.477 with three home runs and 12 RBI in 93 plate appearances.

Late in the season, with the White Sox in a tailspin and a playoff spot secured, Renteria came under fire when he called on reliever Carlos Rodon in a tight spot at Cleveland. Rodon had been sidelined since early August because of a sore shoulder and hadn’t pitched in relief since 2015. But he got the ball with the bases loaded and two out in the seventh inning. And it didn’t go well for him. Rodon gave up a two-run single to Cesar Hernandez and two-run double by Jose Ramirez, sending the Indians to a 5-4 victory.

However, Hahn said Renteria’s performance late in the regular season and in the postseason was not a deciding factor in letting him go.

“This isn’t about any of the decision-making in Game 3 of the wild card series. This isn’t about anything that happened over the last couple of weeks after we switched our position into the playoffs. This is, again, based upon where we are as an organization, and what we need to do to take that next step in putting us in the best position to succeed,” he said.

Rather, Hahn suggested the White Sox were considering a change of direction well before the 2020 playoff run

“We’ve had conversations, Ricky and I, [owner Jerry Reinsdorf] and Ricky, [executive vice president Kenny Williams] and Ricky, for literally years about how the final stages of this will go, and over the last few months and weeks, Ricky and I have had very candid conversations about where we’re at as an organization, and what we need to do to get to the next level, and again we mutually decided that now is the right time to make a change in that position,” Hahn said.

Renteria first joined the White Sox as bench coach in 2015, and took over as manager in October 2016, after Robin Ventura stepped down.

Renteria, who also managed the Chicago Cubs in 2014, owns a 309-398 (.437) record in his five seasons as a major league manager.

“This is not how we wanted this to end,” Hahn said. “We wanted it to end with Ricky leading us to championships. That was the intent from the start. Over time, through very candid and quite frankly personal conversations about where this organization is, what our time horizon is, what we need to do to win in October and get to that final, ultimate goal, it became evident that it was time to make a change.”

Renteria now has the dubious distinction of being dismissed by both the Cubs and White Sox. The White Sox will certainly hope they have similar success after Renteria’s departure as the Cubs did, winning the World Series two years after Renteria was let go on the North Side.

Hahn said Renteria’s replacement likely will come from outside the White Sox. He would like someone who has worked for a championship organization, though major league managing experience is not necessarily a requirement.

“Recent October experience with a championship organization would be ideal, but we’re gonna keep an open mind,” Hahn said.

The White Sox have a long history of hiring first-time managers. Before Renteria – who previously managed the Chicago Cubs – the last White Sox manager who had previous experience managing in the majors was Jeff Torborg, who was manager from 1989-1991.

One candidate Hahn already has ruled out is 2005 World Series manager Ozzie Guillen.

“We love Ozzie, but he’s not the right fit. Jerry called him and told him that,” Hahn said.

Guillen played for the White Sox and led them to a 678-617 record from 2004 to 2011. But his relationship with then-general manager Ken Williams soured.

He has since rejoined the fold as a studio analyst for NBC Sports Chicago and would like to manage again. But Hahn said chairman Jerry Reinsdorf told Guillen on Monday he will not be in the mix for the job.

The White Sox should have their pick of available managers, with a young and extremely talented core of position players and pitchers, and only a few holes to fill in their roster.

“When ultimately we get to where we want to go in terms of winning championships, I suspect Ricky Renteria’s his fingerprints will be all over that, as well, and part of that success will be due to him; a big part of that success will be due to him,” Hahn said.

Shortstop Tim Anderson leads their young core playing under team-friendly deals, having finished second in the American League in batting average in 2020 after winning the AL batting title in 2019.

Veteran first baseman José Abreu is one of the front-runners for AL MVP after driving in 60 runs during the pandemic-shortened season. Lucas Giolito, who pitched his first no-hitter in August, fronts the rotation, and the bullpen has promising options.

Other budding stars on the roster include center fielder Luis Robert, left fielder Eloy Jimenez, third baseman Yoan Moncada, and second baseman Nick Madrigal.

The White Sox could look to free agency to add another starting pitcher. While Giolito and Dallas Keuchel form a solid tandem at the top, the rest of the rotation is a concern for a team with championship aspirations.

Dane Dunning has just eight big league starts after making his debut in August. Dylan Cease struggled with his command this year, issuing 34 walks in 58 1/3 innings. Michael Kopech, one of baseball’s top pitching prospects, opted out of this season because he was dealing with a personal issue. Garrett Crochet, the No. 11 overall pick in the June draft, has yet to make his first professional start.

The White Sox have never been to the postseason in consecutive seasons, but Hahn made it clear he expects that to change in 2021.

“I think it’s perfectly reasonable to believe that we’ve opened our window,” for long-term contention, Hahn said. “We have flaws still. We have holes that we’re going to have to hopefully address over the coming weeks and months, but this is a team that should reasonably have championship aspirations, and I think quite frankly we should be viewed as a very desirable landing spot for potential managers.”

(© Copyright 2020 CBS Broadcasting Inc. All Rights Reserved. The Associated Press contributed to this report.)