DETROIT -- Chicago White Sox owner Jerry Reinsdorf labeled his team's record-shattering losing season "embarrassing" and a "failure" that he said was his responsibility.

Reinsdorf released a letter to fans as the White Sox entered their final game with a 40-121 record, the most losses of any major league club since 1900.

"By all measures, our on-field performance this season was a failure," Reinsdorf wrote. "As the leader of this organization, that is my ultimate responsibility. There are no excuses."

"I want to thank you for continuing to support the team throughout what was an embarrassing season," he added. "You all deserved better. This season's performance was completely unacceptable and the varying reactions and emotions from our fanbase are completely understandable."

The White Sox beat playoff-bound Detroit 9-5 in their finale to finish 41-121.

Chicago broke the post-1900 record for losses, which had been held by the 1962 New York Mets, who went 40-120 during the franchise's inaugural season. The overall big league mark was set by the 1899 Cleveland Spiders at 20-134.

Reinsdorf, 88, headed a group that purchased control of the White Sox in 1981 and the NBA's Chicago Bulls in 1985. The only World Series title under Reinsdorf came in 2005.

"Every blown save, every defensive miscue, every shutout, every sweep -- hurt," he said. "It was a long, painful season for us all. We recognize, on a daily basis, that it is our responsibility to earn your trust, attention, time and support. We vow to take that approach daily as we put the work in this offseason to be better."

Grady Sizemore took over as interim manager on Aug. 8 after Pedro Grifol was fired and guided Chicago to a 13-32 (.289) record -- a 47-115 pace.

"This wasn't the year we wanted and these aren't the numbers we wanted," Sizemore said. "But that doesn't mean this is a total loss. We can build from this and get better."

Sizemore was proud of his team's play down the stretch. Chicago finished 8-6 and won five of its last six games.

That included taking two of three in Detroit against the hottest team in baseball. Those two losses cost the Tigers the second American League wild card and a first-round date with the Baltimore Orioles instead of the AL West champion Houston Astros.

"It isn't just the record, it is the way the guys competed in the last couple of weeks, even the last two months," Sizemore said. "The guys kept fighting, putting the work in and trying to get better.

"This last stretch was really good for us."

Sizemore pointed to a different era for the Tigers, who reached the 2006 World Series three years after losing 119 games.

"Anything can happen in this game, and that's a good example," he said. "We have a lot to improve on, but I think we have the right guys and the right staff in place to get this turned around."

White Sox general manager Chris Getz has said Sizemore will be considered for the manager job.

"Our organization's most important decision in the coming months is to evaluate and identify a new manager and leadership voice for this organization," Reinsdorf wrote. "Chris is well underway with this search. He has identified the key attributes and preferences for our next manager and has already begun an exhaustive search with a wide range of candidates to lead the White Sox in the clubhouse and dugout."