A Spanish magazine on Tuesday printed the names of four riders supposedly linked to Spanish doctors under scrutiny by authorities as part of the so-called "Operación Puerto" blood-doping investigation.

The weekly magazine Interviú said Oscar Sevilla (T-Mobile), Santiago Botero (Phonak) and Ángel Vicioso (Liberty Seguros-Würth) were videotaped with a hidden camera as they entered a Madrid building that housed the clinic of José Luis Merino Batres, a hematologist who authorities suspect ran an extensive blood-doping operation. The story, which used police sources, also linked recorded phone messages from Eufemiano Fuentes, former team doctor of Kelme and ONCE, making references to 2006 Giro d’Italia runner-up José Enrique Gutiérrez (Phonak).

Merino Batres and Fuentes were among five people detained May 23 as part of a three-month investigation dubbed "Operación Puerto." Others included Liberty Seguros-Würth team manager Manolo Saiz, José Ignacio Labarta, assistant sport director at Comunidad Valenciana, and Alberto León, an ex-mountain bike racer.

Teams were quick to react to the news Tuesday. Phonak posted a message on its official web page, while T-Mobile officials said they are requiring riders to sign an affidavit that they have not worked with Fuentes. The Liberty Seguros-Würth web page is no longer available.

"Oscar confirmed to me by phone that he hasn’t had any contact with Fuentes," said T-Mobile team manager Olaf Ludwig. "I have also spoken to Oscar about the latest reports. The doctor he worked with had a clinic in the same building as Fuentes."

As for Phonak, the team released the following statement Tuesday: "The Phonak Cycling Team acknowledges the appearance in the Spanish media of the names of certain team members in connection with Dr. Fuentes. The team management takes these reports seriously, although it has not yet been possible to establish the truth of the allegations. The team management is examining the issue internally. Following this, further information will be communicated."

During a raid last week on Merino Batres’ Madrid clinic, authorities seized more than 100 bags of frozen blood, medical equipment and codes allegedly linking blood samples to elite cyclists and other athletes, including soccer players.

Saiz was said to have been found with a cold-bag reportedly filled with treated blood, banned doping products and an estimated 60,000 euros in cash after an alleged exchange with Fuentes. Following the news, the American insurance company Liberty Mutual, parent company of Liberty Seguros, canceled its $8.5-million-per-year sponsorship with the Spanish ProTour team.

Authorities charge that Merino Batres and Fuentes worked together to extract blood from athletes, treat it to separate valued red-blood cells and then store it for later reinjection. Undetectable by established anti-doping tests, autologous blood doping has become increasingly popular among elite athletes as other products, such as the banned blood booster EPO, have been become easier to detect.

The sting has created a sensation in Spain and threatens to become the worst doping scandal to face cycling since the 1998 Festina affair.

Those implicated won’t face jail time, however. A strict new anti-doping bill that would make doping in sport a federal crime, much along the lines of measures already on the books in Italy and France, isn’t expected to be signed into law until the fall.

In other news, the team formerly known as Liberty Seguros-Würth will start Wednesday’s Euskal Bizikleta race in northern Spain riding in a blue jersey that simply reads "Würth," with the Liberty Seguros name removed.

The German toolmaker announced Monday that it would honor its sponsorship deal with the team, which is set to conclude at the end of 2006 racing season. Würth paid an estimated 20 percent of the team’s budget. Liberty Seguros, meanwhile, announced last weekend it would pay all staff and riders’ salaries through the end of 2006.

"The Würth group signed a contract that’s valid until the end of 2006 with the cycling team, property of Active Bay and directed by Manolo Saiz," a communique read. "According to the culture of our business, outstanding contracts will be fulfilled. If the team of Manolo Saiz is excluded from any competition, the contact will be immediately annuled."

Team Würth will line up in the Spanish town of Eibar with Joseba Beloki, David Etxebarria, Aaron Kemps, Aitor Osa, José Antonio Redondo, Carlos Abellán, Assan Bazayev and Vicioso.

Meanwhile, the whiff of scandal doesn’t seem to be stopping other potential sponsors from stepping up. According to the Spanish daily El Correo, a Kazakh gas company might step in as a co-sponsor through at least the end of 2006. A deal could be officially announced in time for the team to start the Dauphiné Libéré this weekend in France. Kazakh rider Alexandre Vinokourov is the team’s top hope for July’s Tour de France.