The first rule of Davis Cup is don’t talk about Davis Cup lineups.

At least, not in any meaningful sense.

Asked who his singles players will be for this weekend’s World Group first round tie at UBC, Spain’s captain, Alex Corretja, looked at the players flanking him at the press conference and replied, “One of these four.”

Then, just to hammer home the pointlessness of the question, he added with a laugh: “Don’t underestimate Lopez.”

That would be Marc Lopez, one half of Spain’s sensational doubles team and the one player who can clearly be ruled out for a singles match, considering he last played one on tour two years ago.

So, when it comes to Canada’s doubles team on Saturday, for what is often the turning point of a Davis Cup tie, any piece of information must be viewed with a certain skepticism.

Still, it sure sounded convincing at UBC on Tuesday when Canada’s ageless doubles wonder, Daniel Nestor, let it slip that he’ll partner Vancouver’s Vasek Pospisil against Lopez and Marcel Granollers.

“They’re probably the second best [doubles] team over the last year,” Nestor said when asked about the Spanish duo. “They’ve been very consistent. They’ve had bad luck with injuries at inopportune times — in the semifinals of the last two Grand Slams. I haven’t had much success against them, so hopefully playing with Vasek will turn that around.”

Was it an accidental slip? Hard to see that. Nestor has been around the block a few times. A bit of gamesmanship? A vote of confidence?

It felt like the latter, though Canadian captain Martin Laurendeau followed it up with a non-committal response (see rule one).

Nestor will certainly have as much, if not more, say than Laurendeau when it comes to picking his partner.

There was plenty of intrigue around the decision last February against France. Pospisil was announced as the partner at the official draw on the Thursday, but Nestor came out on Saturday with singles stud Milos Raonic instead.

Lineups can change up to an hour before the match.

Based on recent Davis Cup form, there’s no obvious choice. Nestor and Raonic lost in three sets to Julien Benneteau and Michael Llodra in February, effectively ending Canada’s hopes of advancing in that tie.

Then, in the September playoff in Montreal to get back into the World Group for 2013, Nestor and Pospisil fell surprisingly in three sets to South Africa’s Izak Van Der Merwe and Raven Klaasen.

Canada still advanced 4-1, which brought them to this weekend.

Against France, Laurendeau said the decision was largely down to how well Raonic played in his Friday singles romp over Benneteau, and how much Pospisil struggled in his match against Jo-Wilfried Tsonga.

Perhaps Friday this week will again carry significant weight, that is if Laurendeau goes with Pospisil, 22, in singles, as opposed to veteran Frank Dancevic, who showed well against Tsonga in February when Raonic pulled out of Sunday’s singles with swelling in his knee.

And as for that knee, might the way the France tie turned out scare Laurendeau off the idea of using Raonic all three days? Seems plausible.

Pospisil, meanwhile, is coming off a bout of mono in mid-December and hasn’t played a tour match in 2013.

He says he’s feeling great. He lost some weight, but that was the off-season play anyway.

Plenty to chew on.

One thing’s for sure: Laurendeau knows Saturday could be the key to a historic berth in the World Group quarterfinals. Canada would host the winner of Italy and Croatia.

“We’ll spend as much time as we can preparing the doubles,” Laurendeau said recently. “They [Lopez and Granollers] play a bit awkwardly — one guy up and one guy back — so, they’re very tricky to play but, in the end, we believe in our strength.

“Daniel is still a top-five doubles player. He’ll have to play his best tennis. He hasn’t in the last two ties.”

Neither has Pospisil, Canada’s Davis Cup workhorse hero in Israel in September 2011, a victory that lifted them back into the World Group for the first time since 2004.

Pospisil also partnered Nestor at the 2012 Olympics. They lost in the second round, 11-9 in the third set, to No. 3 seeds Nenad Zimonjic and Janko Tipsarevic of Serbia.

Their familiarity should be worth as much as Raonic’s cannon serve.

“Daniel and I didn’t play well against South Africa but that was probably only our one bad match together,” said Pospisil, No. 131 in singles. “We had a tough loss in the Olympics but were just a few points away.

“In South Africa, maybe up 2-0 [in the tie] we were too overconfident and that’s something to learn from. It was just one of those days.

“I’m very eager to go back on the court and I think being so fresh can be a big advantage, even though I haven’t had matches lately.”

Pospisil would love a chance to play hero on home soil this time. He says he’s ready, after admittedly being overwhelmed by the occasion last time out at home.

“I don’t really have any doubts that I’m going to handle it better and better,” he said. “Generally, I feed off the home crowds very well.”

Will he get the chance? Nestor says so. Read into that whatever you will.

mweber@theprovince.com

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