The St. Louis Cardinals officially punched their ticket to the postseason on Sunday at Wrigley Field, and they added insult to injury by making some history along the way.

The Cardinals finished off a four-game sweep of the Cubs on Sunday, winning yet another one-run triumph with a late inning comeback. As if that weren’t remarkable enough, the Cardinals also accomplished something they haven’t done in nearly 100 years.

According to Cubs historian Ed Hartig, the Cardinals swept a four-game series at Wrigley Field for the first time since 1921 by virtue of Sunday’s victory.

Making matters even worse, the Cubs, who are currently stuck in a six-game losing streak, have lost five one-run games in a row. According to STATS Inc, that streak is the longest the team has endured since 1915 when they dropped six consecutive one-run decisions.

The victory helped the Cardinals back to the postseason for the first time since the 2015 campaign, when they won the National League Central Division crown but were eliminated in the Division Series by the Cubs in four games.

The loss eliminates the Cubs from contention for the Central Division title this season, and leaves them four games behind the Milwaukee Brewers and Washington Nationals in the National League Wild Card race with just six games left to play. They could be eliminated from the playoffs as soon as Tuesday night with a loss and wins by the Nationals and Brewers.