Despite again losing time to Jan Ullrich on Saturday’s stage, Lance Armstrong is still in the yellow jersey and seems confident of winning his fifth Tour. Before stage 13 started in Toulouse, he happily signed a number of yellow jerseys as souvenirs for local VIPs and then shook hands with a line of local teenage cyclists who waited for him on the presentation stage.

He signed more yellow jerseys after the finish, and happily answered questions in French for the France 2 network, which covers the Tour live. Then, after being held up during the chaos of finishing another stage in a small ski station, he walked to a helicopter that whisked him down the mountain to his team bus.

The battle between Armstrong and Ullrich could become even more exciting on Sunday’s mountain stage from St. Girons to Loudenvielle. With only 15 seconds separating the two, and with time bonuses of 20, 12 and eight seconds for the first three stage finishers, it’s clear that the German could grab the lead with a similar performance to the one that earned him second place on Saturday’s stage to Ax-3 Domaines. Not since his winning Tour in 1997 — six years ago already — has Ullrich shown the climbing strength he showed Saturday. But the German has to be somewhat concerned that all of his Bianchi teammates were dropped before the final climb, whereas Armstrong still had three U.S. Postal workers to help him there: the Spaniards José Luis Rubiera, Roberto Heras and Manuel Beltran.

When Ullrich won the 1997 Tour, he did it with the huge support of his then-Telekom team colleague Bjarne Riis, who had won the Tour the previous year. And in 2001, when he last challenged Armstrong at the Tour, Ullrich was helped in the mountains by American Kevin Livingston and Kazakhstan’s Alex Vinokourov.

Livingston has since retired. Vinokourov is now himself a strong rival. And, in May, Ullrich lost the man he most expected to be his main climbing support rider, Beltran, who signed with Armstrong’s team during the hiatus between the collapse of Team Coast and the formation of Team Bianchi. Without support, Ullrich could be vulnerable on Sunday.

There are six climbs on this classic 191.5km stage 14 through the eastern Pyrénées that culminates with the Col de Peyresourde, just 11.5km from the finish. There are three climbs in the last 70km, the most difficult one being the narrow, winding Col de Menté, which averages 8.2 percent for 7km. This will soften up the field for the 8.3km Col du Portillon (that comes during a short incursion into Spain), and the 13km Peyresourde, from which the race plunges to the finish in Loudenvielle.

All these climbs have been included in previous Tours, but often in the opposite direction, and sometimes as a prelude to a mountaintop finish elsewhere. In fact, the downhills have often played a bigger part than the climbs, sometimes tragically.

It was on the ultra-steep descent of the Portet d’Aspet (the third mountain on Sunday’s stage) that Italian Fabio Casartelli met his death in 1995. Spain’s Luis Ocaña, when leading the 1971 Tour, crashed out of the race during a thunderstorm on one of the lower switchbacks of the Menté descent. And a couple of years ago Ullrich himself fell into a creek coming down the Peyresourde — if that happens Sunday, don’t expect Armstrong to wait, because the finish is only a few kilometers away, not 40, as it was in 2001. Laurent Brochard was the winner of the only Tour stage to finish at Loudenvielle; that was in 1997, the year that Ullrich won the Tour.

Coming between two stages with summit finishes, this should be a day for the polka-dot-jersey contenders to score some valuable points. With that in mind, expect current King of the Mountains leader Richard Virenque, Gerolsteiner’s Austrian champion Georg Totschnig or ibanesto.com’s Juan Miguel Mercado to go on a marathon attack in the early part of the stage, perhaps on the descent of the Col de Latrape (after 35km) or Col de la Core (67km).

The Peyresourde’s uphill will decide who wins the stage, while its descent could split the GC contenders. Will Ullrich be faster than Armstrong? Or will one of them crack before they reach the final kilometers?

The weather is again forecast to be hot and sunny, but Armstrong’s wish for a cooling thunderstorm seems remote. Meteo France says that the clouds will become more menacing as the day wears on, but heavy rainfall isn’t expected until later in the evening. That won’t please Armstrong, who was hoping for the weather to break after his dehydration crisis on Friday.