Zack Gelof doubled home the go-ahead run and scored another in a two-run eighth inning, and the visiting Oakland Athletics sent the Chicago Cubs to the verge of playoff elimination with a 5-3 victory Wednesday afternoon.

Tyler Soderstrom had two hits, including a homer, scored two runs and drove in a pair for Oakland (67-86), which completed the interleague portion of its schedule with a winning record (24-22).

Despite 2 2/3 shutout innings from Justin Steele in a comeback effort, Chicago (77-75) dropped 6 1/2 games out of the final National League wild-card spot, pending later results, with just 10 games remaining.

With the Cubs’ loss, the Milwaukee Brewers (87-64) clinched the NL Central for the second straight season.

A three-run fifth inning had put the hosts in front 3-1 before Soderstrom’s leadoff single triggered a tying two-run seventh for the A’s. Lawrence Butler produced one run with a groundout before Brent Rooker tied the game at 3 with a two-out single.

Gelof’s go-ahead double into the left-field corner in the eighth plated Seth Brown, who started the frame with a single against Nate Pearson (2-2). Gelof took third on Chicago’s late relay throw to the plate.

One out later, Gelof dashed for the plate on a one-hopper to Cubs second baseman Nico Hoerner and barely beat a strong throw with a slide. Chicago challenged the call, but the safe ruling was upheld.

Tyler Ferguson (4-2) pitched a scoreless seventh, Michel Otanez worked a perfect eighth and Mason Miller tossed a hitless ninth to record his 27th save.

Four Oakland relievers combined for 4 1/3 hitless shutout innings in relief of Brady Basso, who was charged with three runs on six hits in 4 2/3 frames. He walked two and struck out five.

Returning from a strained left arm, Steele threw 57 pitches before he was lifted two outs into the third inning of a scoreless game. He allowed two hits and three walks and struck out one.

Dansby Swanson and Seiya Suzuki had RBI singles and Cody Bellinger a sacrifice fly in the Cubs’ three-run fifth.

Soderstrom opened the scoring with a two-out solo shot in the fourth against Ethan Roberts.

Rooker finished with two hits, as did Swanson and Hoerner. Oakland outhit Chicago 9-6.