The divorce between John Chavis and LSU is getting awfully messy.

Chavis, LSU’s former defensive coordinator and the new defensive coordinator at Texas A&M, fired back at his former employer Friday in a stern amendment to the lawsuit he filed against LSU two weeks ago.

In the amendment, filed in 272nd District Court in Brazos County, Texas, Chavis claims LSU owes him more than $205,000 in unpaid incentives and vacation time and that the school unlawfully doctored his 2012 contract, making it void.

Meanwhile, LSU filed its own amendment to a lawsuit it filed two weeks ago. The school is seeking answers for Chavis’ involvement with Texas A&M before A&M officially announced his hire Feb. 13. The school served, or plans to serve, Chavis with the motion of discovery, according to documents filed in the 19th Judicial Court in East Baton Rouge Parish and obtained by The Advocate late Friday night.

The amendments come two weeks after Chavis, in the initial lawsuit, asked a judge to decide whether he owes a $400,000 buyout to the school. LSU countersued the same day, filing its lawsuit in East Baton Rouge Parish, claiming Chavis owes the buyout for breaching his contract.

In the new filing, Chavis continues to claim that he owes no buyout, but he also argues the university owes him back pay, unlawfully altered his contract and breached the deal in multiple ways.

LSU officials declined comment Friday night, but they answered in court with their own amendment.

LSU’s amendment to its suit centers on the timing of Chavis’ departure from LSU, a key matter in whether he owes his buyout to the school. If he left before Feb. 1, Chavis owes a $400,000 buyout, according to his contract. If he left after Jan. 31, he owes no buyout.

Texas A&M agreed to pay any buyout Chavis owes — a reason the school was included in his first suit — but the school, like Chavis, contends he doesn’t owe a buyout.

A&M and Chavis claim he did not begin work for the Aggies until Feb. 14 — despite evidence to the contrary.

Chavis is seen in a host of photos posted on social media decked in Aggies gear and recruiting for the school starting in mid-January. According to photos and reports from The Houston Chronicle, Chavis landed in a private jet with coach Kevin Sumlin on Jan. 1, two days after LSU’s Music City Bowl loss.

LSU raises these questions in the document of discovery, which includes the previously mentioned photographs of the coach on the recruiting trail and at the airport with Sumlin. The coach is expected to receive the documents from LSU next week and must return them with answers in 30 days.

Chavis’ amendment paints a clear picture of Chavis’ final days at LSU and why he left. After the 2014 regular season ended, head coach Les Miles, Chavis and Athletic Director Joe Alleva began negotiations for an extension, the suit says.

“By mid-December 2014, an impasse occurred” in negotiations because of what’s been referred to as “the Les Miles clause.”

Chavis, the suit says, refused to sign his new contract because of the clause, which “would allow LSU to terminate Chavis’ employment in the event Les Miles’ employment (is) terminated with LSU.”

The Advocate has reported since late December that Chavis left because of the Miles clause — new to his contract but also in every other staff member’s deal.

The amendments again shine the spotlight on a nasty split between the coach and the school that began in mid-December, the new documents say. Chavis left the program after six years for Texas A&M, a Southeastern Conference Western Division rival.

Texas A&M and LSU met for the first time last year in what is expected to be an annual season-ending duel in a somewhat forced rivalry, sparked by the Aggies joining the league in 2012. There is another duel playing out in court documents.

Chavis’ newest filing reveals a serious allegation against LSU. The coach says an LSU employee altered the wording of the termination section of a three-year contract extension he signed in 2012.

Changes, the suit says, were made in the contract between the time he signed it (April 2012) and when it was approved by the LSU Board of Supervisors (June 2012). The suit refers to the doctored version of the contract as “the Alleva amendment,” and the suit says the contract was “intentionally altered.”

“These material alterations were made by some person or persons at LSU for the benefit of LSU and to the detriment of Chavis,” the suit says. “Chavis was not informed of the alterations after they were made by LSU nor did he agree to ratify the alterations after they were made by LSU.”

Because of the supposed unapproved modifications in the contract, Chavis claims the contract is void and thus he owes no buyout.

“After Dec. 31, 2011, Chavis became an employee ‘at will’ and thus no longer subject to any specific terms or conditions,” the suit says.

In addition, LSU has withheld $90,000 in academic incentives earned by Chavis, the suit says. The school paid academic incentives to other staff members, according to the suit.

Chavis argues that LSU breached its contract with the coach on two accounts. One, it paid the coach vacation compensation based on Chavis’ original $550,000-per-year salary and not on his new contract. He claims he has $115,000 in unpaid vacation pay — a total of $205,384 owed to the coach.

LSU also breached its contract with Chavis when Alleva, on Jan. 2, sent a letter to Chavis requesting he pay a $400,000 buyout, the suit contends. The letter came a day after Chavis landed with Sumlin at a College Station airport.

“Chavis, contrary to Alleva’s assertion in the Jan. 2 letter, had not yet resigned,” the suit says. “Alleva’s letter demanding that he pay liquidated damages prior to his actual resignation constitutes a termination by LSU of Chavis’ employment.”

Chavis seeks a judgment from the court to determine the validity of the two amendments — the one he signed and the “Alleva amendment” — and recovery of the more than $205,000 in damages.

LSU just wants answers from the 58-year-old coach.

In its motion of discovery, LSU questions Chavis’ comments to the Houston Chronicle after landing at the College Station airport Jan. 1, specifically this one: “There’s a great opportunity to win big” at Texas A&M, the suit says.

Chavis did not participate in any meetings with the LSU football coaching staff or recruiting events in January, the suit says. Meanwhile, Chavis introduced himself as the A&M defensive coordinator and recruited a host of prospects for the Aggies during January — when he claims not to have started his new job — documents say.

The suit names recruits, including Daylon Mack, a Texas defensive tackle who eventually signed with the Aggies, and Dwayne Thomas, a linebacker from Hahnville who also eventually signed with A&M.

The documents also ask for dates and times for all communication between Chavis and A&M starting Dec. 1, 2014. LSU, in the suit, also wants to know when Chavis was provided with security access to Texas A&M’s facilities, and when he received an A&M email address and school-issued cell phone.

Two of the requests in the discovery document are as follows:

“Does Chavis contend that he was still employed by LSU during the month of January 2015? If yes, then please list all facts and evidence, along with the full names and addresses of any witnesses, in support of that contention.”

“Does Chavis contend that he was not employed by Texas A&M during the month of January 2015? If yes, then please list all facts and evidence, along with the full names and addresses of any witnesses, in support of that contention.”

Follow Ross Dellenger on Twitter @DellengerAdv.