OAKLAND -- A knee injury delayed Chris Herrmann’s regular-season debut with the A’s, but once it came around, he wasted no time endearing himself to the Coliseum faithful.

Called up from Triple-A Las Vegas on Tuesday upon completion of his rehab assignment, Herrmann was inserted into the starting lineup and immediately made an impact in the fourth inning by blasting a fastball from Twins starter Jake Odorizzi over the wall in center for a grand slam in his second at-bat. It was the catcher’s first hit as a member of the A’s and second career grand slam, putting Oakland ahead by three in an 8-6 victory. He became the first player in franchise history to hit a grand slam in his debut.

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“When you hit a home run, period, let alone a grand slam, it makes you feel like you belong pretty quickly with the team,” A’s manager Bob Melvin said. “It was nice to get him off to a good start. He catches a win and draws a walk, a lot of things that we profiled him to do.”

Through a grueling rehab process from knee surgery that saw him go through months of inactivity, there was a point where Herrmann was close to resigning himself to 2019 being a lost year. Once he connected on the blast, his trip around the bases was a whirlwind of emotions.

“It felt amazing. It’s been a grind. I can’t thank my family enough for all the support that I’ve had over the past three months,” Herrmann said. “There was times where I didn’t even think I was going to play this year. My teammates and coaches were behind my back. To come out and hit a grand slam in my first game is just awesome.”

Herrmann was greeted with chants of “Herr-mann!” from the crowd of 13,423 fans as he returned to the A’s dugout, where he received a hero’s welcome by his teammates.

“For all the fans to welcome me like that after my grand slam was a really great feeling,” Herrmann said. “I know we don’t have a ton of fans here, but the ones that do come are loyal and care about baseball. I don’t care if the seats aren’t packed, it’s just all about the loyal fans here in Oakland. It’s a fun place to play with the music in right-center and left-center. These guys are into it.”

Not only did Herrmann impress at the plate, Melvin was also pleased with his ability to work with the four pitchers the A’s used on the night. It’s no easy task, especially for Herrmann, whose time with A’s pitchers was limited in Spring Training with the injury occurring just a couple of weeks after the start of Major League camp.

“You get through a game like that with most of our plus-guys and it’s learning on the fly,” Melvin said. “He did a good job.”

Signed to a one-year deal with the A’s in December, the left-handed hitting Herrmann is expected to get some time against right-handed pitchers behind Josh Phegley, who has emerged as the everyday starter with a solid first half. He hit .333 with four home runs and 13 RBIs in 13 games on a rehab assignment at Triple-A Las Vegas.

“I was pretty surprised at how quickly I got into a groove,” Herrmann said of his success at Triple-A. “I wasn’t trying to do a whole lot. Just hitting the ball opposite field a ton, and tonight with the bases loaded like that, I didn’t want to do too much. Usually, whenever we do that as players, it makes it easy.”

The grand slam was one of the three A’s home runs on the night as they engaged in a mini Home Run Derby with the Twins, who also hit three. The power display came as no surprise with Oakland (85) and Minnesota (89) the top two home run-hitting teams in the Majors dating back to May 13.

Matt Olson clubbed a two-run homer off Odorizzi in the third, his 17th of the season, and Mark Canha blasted a solo shot over the wall in left off Matt Magill in the seventh.

Hendriks nails it down

Liam Hendriks shut the door on Minnesota in the ninth as he struck out two of the final three batters he faced following a leadoff single by Miguel Sano to record his third save of the year. The right-hander capped off a solid night from the trio of Hendriks, Yusmeiro Petit and Joakim Soria, who combined to hold the Twins to one run over the final 3 1/3 innings in relief of starter Daniel Mengden.

With A’s closer Blake Treinen on the injured list and Lou Trivino getting a temporary switch to lower-leverage situations as he works through some struggles, Petit, Soria and Hendriks have been relied on heavily to pick up the load in the bullpen. Each has done their part, with Hendriks coming off a June in which he posted an impressive 0.60 ERA over 14 appearances.

“It was key that Mengden was able to get into the sixth,” Melvin said. “Petit had to come in and do his thing for one-plus innings like he’s done so many times. He continues to perform in high-leverage situations. Soria has also been pitching really well. It’s been really important for him to fill the void late in games and he’s done that.”

Luzardo leaves start early

A’s No. 1 prospect Jesus Luzardo was thought to be on the cusp of a Major League callup, but that could be pushed back after Tuesday night. The left-hander was originally scheduled to throw six innings and around 90 pitches, but was pulled after four innings due to tightness in his left lat muscle. Luzardo will be re-evaluated on Wednesday.