Lindenwood Professional Athletes

Geoff Hartlieb is in the big leagues this September, and someone else had to go to make room.

The Lindenwood product earned a spot on the Oakland Athletics' active roster last week when the club selected his contract, a move that directly triggered the designated-for-assignment — and ultimately the release — of left-hander José Suarez. It's the kind of transaction that gets one paragraph in the transaction wire, but for a Lindenwood alum carving out a bullpen role at the MLB level, it's anything but routine.

Suarez, 28, had been shuttling between Sacramento and Oakland since mid-May after the A's acquired him in a cash deal with Seattle. He worked in low-leverage spots and was expendable when the A's needed a fresh arm. That arm was Hartlieb's.

On the Mound

Hartlieb wasted little time making his case. In his first outing of the stretch, Sunday, September 6 against the Mariners, he worked a single inning, struck out two, and allowed one earned run in a 6–2 Oakland win — a serviceable debut in what was ultimately a comfortable game. His ERA sat at 5.09 after that appearance.

He answered with a sharper effort Wednesday, September 9, against the Blue Jays, turning in a clean two-inning stint with two more strikeouts and no runs allowed in a 2–4 Oakland loss. That performance brought his ERA down to 4.58 — not dominant, but the trajectory is the right one. Two outings, three innings, four strikeouts, and a team willing to trust him in a real MLB bullpen situation.

The Bigger Picture

For Lindenwood, a Division I program out of St. Charles, Missouri, that only recently transitioned to the top tier of college athletics, Hartlieb's September presence on an MLB roster is a genuine milestone. He's not just passing through — he's pitching in back-to-back weeks against legitimate competition, accumulating outs, and holding his own in a league where roster margins are razor thin.

The A's, deep in a rebuild and playing out the string in 2026, have used September to audition fringe roster options. Hartlieb has so far done enough to stay in the conversation. Whether he finishes the season in Oakland or gets shuffled back down, the fact that his selection came at the direct expense of a 28-year-old MLB veteran says something about how the organization views his upside.

Lindenwood fans don't get many chances to follow one of their own on a nightly MLB box score. This is one of those windows — and Hartlieb is making it count, two innings at a time.

Lindenwood Alumni Report | MLB | Aug. 30–Sept. 5, 2026

Geoff Hartlieb is back in the big leagues — and he's making the most of the opportunity.

The Lindenwood product had his contract selected from Triple-A by the Oakland Athletics last week, earning a spot on both the active and 40-man rosters after the A's designated left-hander José Suarez for assignment. For a pitcher who has had to grind his way back through the minors, getting that call is the kind of moment that matters.

Hartlieb logged two appearances during the week, giving Athletics fans a look at what the righty brings to a bullpen navigating the final stretch of the season.

Sept. 2 vs. Rangers: Hartlieb turned in a clean 2.0 innings of work against Texas, striking out one. It was a steady, low-drama outing — exactly the type of performance a freshly called-up reliever needs to prove he belongs.

Sept. 5 vs. Mariners (A's 7–5): Oakland picked up a win over Seattle, and Hartlieb contributed 1.1 innings with another strikeout. His ERA settled at 4.86 on the week — not eye-popping, but workable for a reliever still shaking off Triple-A rust in high-leverage September situations.

The timing of the roster move carries some symmetry worth noting: Suarez, the pitcher Hartlieb effectively replaced, had himself arrived in West Sacramento via a cash deal with the Mariners — the same team Hartlieb faced in his second outing of the week. Oakland's bullpen carousel keeps spinning, and for now, the Lindenwood alum holds a seat.

Whether Hartlieb sticks through the end of the season will depend on continued performance, but the baseline is established. Two appearances, 3.1 innings, no major disasters — the kind of debut week that keeps a pitcher in the conversation.

For Lindenwood fans, it's a name worth tracking on the MLB transaction wire. Hartlieb's path from a small program in St. Charles, Missouri to an active MLB roster is the kind of story that doesn't get old.