SAN FRANCISCO -- On one hand, this is a four-game series straddling the end of August and the start of September, so there is a lot of regular season baseball left to play and every series is important and every other clich¨¦ you can conjure. That¡¯s how both managers chose to view this meeting of the Brewers and Giants at Oracle Park.

On the other hand, these are two division leaders who hope to meet again in October. These games are important. So, Milwaukee first baseman Rowdy Tellez eschewed the clich¨¦s and embraced the hype before the teams delivered a series opener worthy of it -- a 3-1 Brewers win on Monday, complete with a chill in the air.

¡°This is huge,¡± Tellez said on the eve of the series. ¡°I think this is going to be a showdown coming into the playoffs. This is going to be a big series for us. It¡¯s going to test us. We¡¯re going to test them. ... I think we can take a series.¡±

The Brewers took the series opener behind Corbin Burnes, who pitched into the seventh inning, struck out nine and singled home a run as Milwaukee led wire to wire in what was a bullpen game for the Giants after San Francisco placed starters Johnny Cueto and Alex Wood on the injured list.

Burnes carried a 2-0 lead into the seventh inning, when Brandon Belt doubled over Avisa¨ªl Garc¨ªa¡¯s head to spark a Giants rally that brought reliever Brad Boxberger into the game. He allowed one inherited runner to score, but that was it, and Devin Williams and Josh Hader finished the Brewers¡¯ 80th victory.

¡°That was definitely a playoff atmosphere and something that could be foreshadowing what we see in the postseason,¡± Burnes said. ¡°It¡¯s always good to get the first one of the series. That was definitely a big one tonight.¡±

Hader¡¯s radar gun readings showed how big. He topped out at 98.9 mph, the hardest the Brewers' closer has thrown since he threw a pair of fastballs north of 99 mph on Opening Day.

¡°I think this is a fun place to play,¡± said Brewers manager Craig Counsell, who knows a bit about that from his own playing career. ¡°There's really good atmosphere here. There's good fans here who make it feel like a big game. I think Josh felt it too.¡±

Good bullpens are critical in October, and the Brewers¡¯ back-end trio of Boxberger, Williams and Hader have been getting stronger of late. In August, they have combined for a 0.25 ERA with 55 strikeouts versus seven walks in 36 2/3 innings. They have stranded seven of 11 inherited baserunners in that span, including Boxberger¡¯s work to keep Kris Bryant planted at third base in the seventh inning on Monday night when Bryant represented the tying run.

That came after more good work from Burnes, who was charged with one run on four hits in six-plus innings, with no walks and nine strikeouts. He lowered his ERA to 2.27, second-best among Major League qualifiers to the Dodgers¡¯ Walker Buehler (2.02). Burnes leads qualified MLB pitchers in strikeouts per nine innings (12.24), strikeouts to walks ratio (7.27) and FIP (1.58).

"I don't even know what to say. I thought I was getting away from him coming over here, but I¡¯ve seen him twice now [as a Giant],¡± said Bryant, the former Cub who was traded to San Francisco at the Trade Deadline. ¡°He's one of the best in the game. He's got five ¡®plus¡¯ pitches and throws strikes, and when he's not throwing strikes, it looks like it's going to be a strike.¡±

Said catcher Omar Narv¨¢ez, who drove in the Brewers¡¯ run in the first inning before Burnes singled home another in the second: ¡°He was under control today. I think he was more thinking through me, rather than trying to throw as hard as he can.¡±

Giants hitters didn¡¯t make it easy. After Burnes breezed through two perfect innings on 22 pitches, the Giants coaxed 23 pitches in the third. But Burnes kept them off the scoreboard until the seventh.

¡°I¡¯m more mentally tired after facing those good hitters,¡± Narv¨¢ez said. ¡°Corbin made things easier by throwing strikes and being ahead of almost every hitter he faced. Corbin can be really dangerous when he¡¯s ahead [in the count]. That was the whole key today.¡±

Likewise, Brewers hitters made things as difficult as possible for a Giants team facing a pitching scramble after losing each of its scheduled starters for the first two games of the series. Seven San Francisco relievers covered Monday¡¯s nine innings.

¡°Guys got looks against all their bullpen guys. I think that's valuable,¡± Counsell said. ¡°I look at it like they had to spend a lot of resources tonight, and hopefully we can make that good for us later in the series.¡±