Inside the two-story Thistle & Grouse at 10 Cotton St. in Portland. Courtesy of Thistle & Grouse

Insurmountable money problems have forced Old Port upscale gastropub Thistle & Grouse to close its doors for good, just 10 months after launching, according to the owner.

The two-story, 5,000-square-foot restaurant opened last December at 10 Cotton St., the location of the former Rivalries sports bar.

Chef-owner Bobby Will said Friday that the restaurant closed “quietly” as of last Sunday, though he announced the development on Instagram Friday.

Will and co-owner Kimberly Kraus took over the space in February of 2023, aiming to launch by July or August of 2023, because they figured it would simply need cosmetic upgrades. “We were sold on it being turnkey, and it was not,” he said. “We were met with hurdles from the minute we started the process.”

Will said they had to update the restaurant’s electrical and plumbing systems and add sprinklers and fire alarms. “It all went downhill from there, and it slowed us down significantly,” he said. “We ran horribly over budget. We were financially drowning from the get-go with the build-out.”

The financial climate of the past winter added to their challenges, Will said.

“We trudged through a really rough, slow winter, with inflation making people unable to dine out as much as they had in the past,” Will said. “When wallets are tight, people usually go to places that they know are safe bets, and because we were the new kids on the block, maybe it felt like a risk.”

Will said he and Kraus had taken part-time jobs earlier this year in an effort to augment their finances and help keep the restaurant afloat. “We were literally living week to week,” he said.

Will and Kraus had run the Bar Harbor restaurant Salt & Steel for five years before closing it in 2023. Will had previously been executive chef at Saltaire Oyster Bar and Fish House in Port Chester, New York, which earned an “excellent” rating from the New York Times under his leadership. Will had also worked under renowned chefs like Jean-Georges Vongerichten and Boston-based chef Andrew Husbands.

Portland Press Herald dining critic Andrew Ross gave Thistle & Grouse a 3.5-star review in March.

“We had great reviews, and everybody that came in there really liked what we did, so I don’t think it was a folly,” Will said of Thistle & Grouse. “I’m not sure if my concept wasn’t clicking and maybe something more casual would have worked out better there. But we set out with a vision and we were trying to stick to it, because we didn’t want to waver. ”

The business is listed for sale on the New England Property Exchange.