PHOENIX — Tensions are rising between Maricopa County and the Arizona Diamondbacks amid lease renewal negotiations at Chase Field, with team officials calling a recent letter they received from the county “deeply unpleasant” and county officials saying the team's latest proposal is “neither realistic nor feasible.”

The team is in negotiations with Maricopa County, which owns Chase Field, over a lease extension because the team's lease expires in 2027. The new lease term and the cost of much-needed renovations are not reconciled. The team has said it is willing to put a lot of money into renovating Chase Field, but recently received a counteroffer to its previous proposal that would have included a 50-year lease and $150 million in stadium maintenance costs.

“We find this letter extremely offensive, especially since we have come to the table with hundreds of millions of dollars invested in renovations to a ballpark we don't own and the county has not provided any funds,” a Diamondbacks spokesman said. “Asking us to sign a 50-year lease renewal for a ballpark we don't own when we are the only ones actually putting the money into it is neither a serious nor logical proposal.”

In a letter, the Maricopa Board of Supervisors called the team's previous proposal, which included a 10-year lease with a short-term option to end the lease, “neither realistic nor feasible.” The letter also criticized the team for failing to keep the stadium safe for fans.

“The current MOU clearly places responsibility for maintaining the building on the team,” the letter states. “Reports of falling concrete and high heat indicate that those responsible for the building may not be taking the necessary steps to maintain a safe and comfortable environment.”

A Maricopa County spokesperson said they were pleased with the progress being made in the negotiations and released the following statement:

“Maricopa County is pleased with the progress in our ongoing negotiations with the Diamondbacks and is optimistic that we can reach a mutually beneficial agreement that benefits all stakeholders – the team, the fans and the taxpayers. Our goal is to find a long-term solution that keeps the Diamondbacks downtown and preserves the lifespan of Chase Field, a public asset. We believe our recent proposal is fair and balances the flexibility the Diamondbacks need with the necessary investment in Chase Field. It is our goal that the Diamondbacks will play baseball in downtown Phoenix for decades to come.”

Chase Field is the fourth-oldest ballpark in the National League, but its problems go beyond leaking pipes.

“When you look at the new ballpark, its office space, the hotel, the restaurants, there are benefits for us, whether that's downtown or somewhere else,” Diamondbacks CEO Derrick Hall said in February. “Where are the opportunities for us? That's another thing we're discussing internally, because we want to create a vibrant place around the ballpark 365 days a year.”

The stadium's roof still hasn't been repaired; it can be opened and closed, but only when there are no fans present. Attendance is an issue for a team that has made the playoffs just once in 11 years; the Diamondbacks have ranked near the bottom of the National League since 2005.

The team said it would continue to “explore a solution” in future negotiations.

Here is the team's full statement:

“We found this letter extremely offensive, especially since we have committed hundreds of millions of dollars to help renovate a ballpark we don't own, and the county has provided no funding at all. We have worked with a broad range of supporters here in Phoenix to try to work in true teamwork. We have done our part all this time by investing millions of dollars in renovating this aging ballpark, but have received very little support. Truth and fairness are important here, and bizarre attacks like this are not the way our partners should do business. It is clear to everyone that this is a bomb-throwing tactic by the chairman who lost the primary election, and two other outgoing members who will not be participating in any future negotiations. Asking us to sign a 50-year lease renewal for a stadium we don't own, even though we are the only funder, is not a serious or logical proposal. We will continue to seek a solution and appreciate the state and city's continued efforts.”

12Sports' Cameron Cox contributed to this report.

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