Ducks sign veteran defenseman Paul Mara

The Ducks had talked to free-agent defenseman Paul Mara before they learned Toni Lydman will miss the start of training camp after experiencing acute double vision. But their signing of Mara on Thursday was good timing for a team piecing its defense together after trading Chris Pronger and losing Scott Niedermayer to retirement in successive years.

Lydman, who signed a three-year, $9-million contract in July, fell ill last week during a post-workout lunch with teammates. He called fellow Finn Teemu Selanne, who alerted the team doctor. “They’ve been doing tests ever since,” Ducks General Manager Bob Murray said.

Several causes have been ruled out, but no explanation has been found. Murray said doctors are checking whether a history of occasional migraines might be related to Lydman’s vision problems, which have eased.

Mara, a well-traveled 31, played 43 games with the Montreal Canadiens last season before tearing the labrum in his shoulder. He had surgery in March. Ducks doctors tested him before he signed a one-year, one-way deal for $750,000.

“We looked at the Ducks as the best place for me as a person, as a hockey player and a chance to win,” Mara said.

The Ducks also signed forward Stephane Veilleux to a professional tryout contract. “We’ve liked him in kind of a hardworking, penalty-killing role,” Murray said.

Players report for physicals Friday and will practice Saturday at Anaheim Ice.

helene.elliott@latimes.com