WASHINGTON — Sen. Ted Cruz and Rep. Beto O'Rourke have agreed to three debates, with the first of the high-stakes confrontations set for Dallas on Friday, Sept. 21.

The hour-long debate will be hosted by The Dallas Morning News, Southern Methodist University and KXAS-TV (Ch. 5). The campaigns announced the event on Friday afternoon.

Texas has emerged as a major battleground in the 2018 midterms, and both contenders have much to gain or lose.

This will be the first of three televised face-offs the rivals agreed to hold before Election Day — a chance to show their command of key issues or expose a rival's soft spots, defend their records, amplify their talking points, and paint the other candidate as out of touch with the majority of Texas voters.

All three debates will run one hour.

The second debate will be in Houston on Sept. 30, a Sunday, at the University of Houston. Like the Dallas debate, it will focus on domestic policy.

They'll meet a final time on Tuesday, Oct. 16 in San Antonio for a debate divided evenly between domestic and foreign policy.

For the Dallas and San Antonio debates, the rivals will stand at podiums. The Houston debate will be held town-hall style, with stools available for Cruz and O'Rourke.

Looking forward to three debates with Senator Cruz.

➡Dallas on Sept. 21

➡Houston on Sept. 30

➡San Antonio on Oct. 16 — Beto O'Rourke (@BetoORourke) September 14, 2018

O'Rourke challenged the incumbent to six debates in April. Two months later, after refusing to negotiate, the senator countered with a take it or leave it offer of five debates on Friday nights through October. He picked the dates, cities, topics and formats, and insisted that he wouldn't budge, although he did agree to let O'Rourke replace one of the sites with El Paso since Houston — Cruz's hometown — was already on the list.

O'Rourke rejected the terms. The stalemate persisted for a month.

Under the terms agreed to for the Sept. 21 debate, there are no restrictions on topics that the moderators, political writer Gromer Jeffers Jr. of The News and Julie Fine of KXAS, can cover.

The campaigns will control tickets for the debate to be held at SMU's McFarlin Auditorium.

Senator @TedCruz and Congressman Beto O’Rourke to Hold Three Debates in Dallas, Houston, and San Antonio Leading Up to the 2018 Senate Election: https://t.co/z5EavTKyjg #TXSen — Team Cruz (@TeamTedCruz) September 14, 2018

"This race has important implications for the future of Texas and the country," said Mike Wilson, editor of The Dallas Morning News. "We are proud to join with NBC 5 and SMU to help provide the information voters need to make their choice, and we commend Sen. Cruz and Rep. O'Rourke for participating."

Friday's debate will be broadcast live at 6 p.m. on NBC 5/KXAS and livestreamed at NBCDFW.com and dallasnews.com.

It will be rebroadcast Sunday at 8 a.m.

The format will keep the rivals on their toes: 90-second answers, a 60-second response from the other debater, then a 30-second rebuttal to that response.

O'Rourke has put a scare into Republicans by overtaking the incumbent in fundraising and battling him to a tie in recent polls, or close to it. But the hundreds of questions he's fielded at town hall-style campaign events in recent months may not prepare him for the glare of live television and the rapier style of the incumbent.

Cruz, a champion debater at Princeton University, excelled as an appellate lawyer after Harvard Law School. He argued nine cases before the U.S. Supreme Court and has 20 presidential debates under his belt from the 2016 primaries.

The prospect of five or six debates had startled campaign watchers around the country. Incumbents typically view debates as risky and try to avoid them, and having so many debates would be unusual even in a contest for an open seat.

Cruz's willingness to entertain so many debates likely reflects confidence in his own debating skills — and a calculation that he can use the platforms to pierce O'Rourke's aura of affability.

Even after Labor Day, the challenger and his views remain relatively unknown to many voters, whereas Cruz, a national force for six years, has near universal name recognition in Texas and even around the country.

O'Rourke had prodded Cruz to agree to schedule debates other than on Friday nights, when many Texans are focused on high school football.

He had also proposed holding one debate in Spanish, which would give him a clear edge. Having grown up along the border, he is bilingual, unlike Cruz. The senator's father immigrated from Cuba, but his own command of the language is "lousy" by his own assessment, and he rejected his Anglo challenger's gambit months ago.

Most statewide incumbents in Texas — all Republicans — have refused to debate their challengers, though Gov. Greg Abbott has agreed to one debate with former Dallas County Sheriff Lupe Valdez.

The gubernatorial debate is set for Sept. 28 in Austin, also during Friday night football.