MILWAUKEE — In one of the most important games of the year, everything that could go wrong for the Mets went wrong. There were booted balls and errant throws. The Milwaukee Brewers bullied Francisco Alvarez on the basepaths before the catcher left the game with back spasms. Left-hander Sean Manaea, a catalyst in the push for a postseason berth, gave up a first-inning grand slam to frequent Mets tormenter Rhys Hoskins, and Francisco Lindor, playing for the first time in 12 days, didn’t look like himself. The Mets lost 8-4 Friday night at American Family Field, and the Atlanta Braves cruised to an easy win over the Kansas City Royals. The San Diego Padres beat the Arizona Diamondbacks to clinch the top Wild Card spot and home-field advantage in the first round. The Mets (87-71), Braves (87-71) and Diamondbacks (88-72) are all vying for the remaining two spots. Mark Vientos hit his 27th home run off right-hander Frankie Montas in the third, a two-run shot that cut the Milwaukee lead to three runs. It was the lone bright spot in the game. It was the second straight loss for the Amazins’ and while two isn’t necessarily a reason to sound the alarm, it was two sloppy losses in two key games. The Mets allowed six stolen bases, threw two wild pitches, had a passed ball and an error defensively, and at the plate they went 0-for-6 with runners in scoring position. “They outplayed us today,” Lindor said. “I make an error, and they end up scoring. They ran the bases better than we did, they hit better than we did, they hit with runners in scoring position. Overall, I know the Brewers played better than us today. Tip my cap to them, come back tomorrow ready to win.” Alvarez was injured in the top of the seventh, sliding into third base. He grabbed his back and walked off the field with the help of a trainer and was replaced by Luis Torrens. However, he received treatment following the game and was able to walk and move around. The Mets aren’t ready to say he’ll play again Saturday, but they don’t seem overly concerned. “My body is doing way better, I just feel a little tight,” Alvarez said. “We’ll see tomorrow how it’s going to feel and if I can play.” As bad of a start as the Mets had, they still kept fighting. Down 5-2 in the top of the fourth, Alvarez battled Montas for 10 pitches with two on and two out. The catcher laid off a pitch just below the zone with the count full and dropped his bat thinking Montas threw him ball 4, but home plate umpire Ramon De Jesus called it strike 3. Manager Carlos Mendoza was promptly tossed for arguing balls and strikes. Mendoza said his intention was to protect Alvarez, but the Mets had been unhappy with the zone De Jesus was calling since the first inning. The same borderline pitches that were strikes for Montas and reliever Joe Ross were balls for Manaea, which led to bad counts and too many pitches thrown in the early innings. “They have a tough job and I know they’re working really hard,” Mendoza said. “I didn’t agree with it. I thought he didn’t have a good game behind the plate. Not only was it that call, there were some other calls that I wasn’t happy with. But again, I know they’re trying and we’ve got to move on.” Even when things went right, they went wrong. With two on and two outs in the bottom of the sixth, second baseman Jose Iglesias made a fantastic diving stop on a hard grounder from standout rookie Jackson Chourio just beyond the dirt, flipping the ball to Pete Alonso from his knees. Alonso dove to make the pick a split second after Chourio tagged the base and Brice Turang came home. The Mets challenged the call but it was confirmed on review. Jose Butto then relieved Manaea (12-6), who made his shortest start in more than a month going only 3 2/3 innings. He was charged with six runs (five earned) on seven hits, walking two and striking out one. “I fell behind guys, I wasn’t really throwing my slider for strikes and I don’t think I really threw any changeups for strikes,” Manaea said. “Just all of that.” Turang went 3-for-4 with a double, an RBI, a walk, three runs scored and three stolen bases. The Mets loaded the bases on left-hander Hoby Milner in the top of the eighth with one out. Brandon Nimmo scored on a sacrifice fly and Pete Alonso scored when Turang dropped a fly ball hit by J.D. Martinez. But the Brewers replaced Milner with right-hander Trevor Megill, the brother of Mets’ right-hander Tylor Megill, who induced a rally-killing pop-up to Torrens. Gary Sanchez, the former Yankees catcher who had a brief stint with the Mets last season, put the game away with a massive home run off Alex Young in the bottom of the inning. Lindor went 2-for-4 with a walk in his first game since Sept. 15. He was also charged with an error and looked to be in pain at times, though he said he should be fine to play the rest of the weekend.