OAKLAND -- Nick Allen sat in front of his locker at the Oakland Coliseum, jotting his thoughts into a small yellow spiral notebook. Allen had just finished a pretty good workday in the A’s 5-2 loss to the Padres on Saturday afternoon.

“I do it every day,” Allen said of the notes. “I just try to go over how the day went. I write everything down in there and then put all of my thoughts, talk about my at bats and try to flush it and move on to the next day. …

“Good stuff, bad stuff -- always finish it all on positive notes. Just writing myself some good things because this game’s so negative so you have to find ways to talk positive to yourself.”

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Allen had some good stuff to write down on Saturday. He doubled and scored the A’s first run and also made a couple of nifty plays in the field. Along with second baseman Zack Gelof, who hit his 12th home run since being called up in July, the A’s might have a nice keystone combo going forward.

“We’re working every day, trying to get better together,” Allen said. “We’re living together, so sometimes we drive to the field together. I think we’ve got a good combo up the middle right now.”

Said Gelof, “He’s such a gifted shortstop and player in general. He works his tail off, too. I think we feed off each other in the weight room, in the cages, in the field. We’re always trying to get work done, and once we take the field, it’s ball out. That’s the mentality.”

The A’s fell behind 2-0 in the top of the first when starter Mason Miller struggled with his command. He walked Ha-Seong Kim to start the game, then gave up a double to Fernando Tatis Jr. Juan Soto’s sacrifice fly brought in one run, and Xander Bogaerts singled in another.

Allen hit a one-out double in the third, went to third on a Tony Kemp single and scored on a Ryan Noda sacrifice fly.

Padres starter Matt Waldron, he of the full arsenal and a knuckleball, was cruising through five. But Gelof led off the bottom of the sixth with a deep shot to left. Soto didn’t even turn around to look at it.

“He was doing a good job of dotting pitches all day,” Gelof said of Waldron. “I was trying to be aggressive over the plate, and he hung one. I put a good swing on it, and it went out.”

Gelof also made a nice catch of a line drive behind the second-base bag off the bat of Brett Sullivan in the second.

“This young man,” Oakland manager Mark Kotsay said, “has done a tremendous job since he’s been called up -- both on the offensive side and the defensive side. We saw him make an athletic play on the line drive. I think he’s shown the impact he can have, not just on the field but also in the locker room. He’s come in here and started to become a leader in the clubhouse.”

Allen said his double came off Waldron’s knuckleball.

“I think that’s the first time getting a hit off of a knuckleball,” he said. “I haven’t really seen too many knuckleballs. I think the last one I saw was in High-A. It’s crazy to see on a report, knuckleball.”

Allen said this is the year he has been taking notes full time. He said he tried to do it a little bit last year.

“I really put an emphasis on this off season working on it and mining it into this year,” he said. “It’s been awesome. I think it has helped me so much. Just with the course of the year. I think I’ve shown up every day with a lot of energy and I think that’s a testament to how I finish my day.”