Their relationship was tested in Monaco after Rosberg's controversial off in qualifying prevented Hamilton from a final run at pole, and there appeared to be little love lost between the duo after the German came out on top in a tense race in the Principality to recapture the lead in the drivers’ standings.
Hamilton, however, says that he has talked to Rosberg since that race and recently tweeted a photo of the two of them in their youth, on unicycles, saying that everything is ‘cool’ between them again.
Well, perhaps until the lights go out on Sunday…
The odds clearly favour the F1 W05 Hybrids again this weekend in Montreal, especially with their straight-line pace, and a seventh successive victory seems the most likely outcome. However, recent races in Montreal have thrown up plenty of dramatic twists and turns…
Judging by his past record in Montreal, Hamilton would appear to have an edge over Rosberg - the Briton dismantled then McLaren team mate Fernando Alonso in Canada in his rookie season in 2007 and has added a further two race wins in the country since.
Just behind the silver cars in the current pecking order are Red Bull, who are desperate to score well again and stay in the title fight, hoping that the second half of the season will enable them to catch Mercedes. But after finishing a fighting third in Monaco two weeks ago, Daniel Ricciardo isn’t optimistic about how his RB10 will perform on the radically different Ile-Notre Dame circuit.
"Montreal is still a street circuit but unfortunately the straights go on a little bit longer there (than in Monaco) so we're still down a little bit in that area, which I think everyone's aware of,” he said.
“We've made progress but whether it will be enough by then, honestly, probably not. But we are closing the gap so that's all we can ask for, for now, and just keep chipping away at it and be patient."
Ferrari looked stronger in Monaco, especially when Kimi Raikkonen was running third and staying ahead of Ricciardo. Fernando Alonso has said that the team have spent plenty of the time in the simulator working on set-up for this race and he’s confident that the F14 T will be better again in Montreal.
Lotus, meanwhile, have similar top speed problems to fellow Renault-powered runners Red Bull, but nonetheless had another promising outing in Monaco as Romain Grosjean fought back from a first-lap puncture to finish eighth.
"I have very good memories from 2012 when I went from seventh on the grid to my first second place in Formula One," the Frenchman says of racing in Canada. "It was a really great day and it was really a strong team result as we used a one-stop strategy to get on the podium after a disappointing qualifying session the day before.
“We scored points in Monaco and we know where to improve the car, which is not quick enough in low-speed corners and certainly we're trying to get more power for Canada too! But the aerodynamics are stable and the power unit management is getting better so now we are more focused on the suspension side.
“Last year we had a very good car in that aspect, so we'll compare the E22 with the E21 and possibly revert to some previous settings to make it better at low speed. I believe our downforce is pretty good so it's mechanical grip we're after. We improved the car at Monaco, even if it didn't look like it on the timesheets."
If some teams have underwhelmed over the opening five races of 2014, Force India have over-delivered - and the Silverstone-based team plan to continue their point-scoring run in Montreal.
"The battle for fourth place [overall] is going to be intense as the season develops, but at the moment we are firmly in fourth with a 15-point advantage over fifth place," team principal Vijay Mallya says. "We are now a third of the way into the season and we've shown that we have a car that can constantly deliver, whatever the track. We've been in the points in every race, which is very motivating for everyone in the team and helps pump us up even more. There are some strong teams behind us, but we are holding our own and will continue pushing hard. Canada should be a good one for us."
Fellow Mercedes-powered squad McLaren come to Montreal on the back of a strong race at Monaco, too. They have an impressive record in Canada, with 13 victories, while Jenson Button of course scored that magnificent triumph in 2011 when he drove from last to first and took the lead on the final lap. Rookie Kevin Magnussen, in contrast, will be experiencing the Circuit Gilles-Villeneuve for the first time.
"It was a positive for the whole team to put some points back on the board at Monaco after a difficult few races," Button says. "We're obviously still far away from where we want to be, but it's important that we maintain our aim of continuous development throughout the whole season. Although we're still a long way from the leaders, we've matched the general rate of development since the start of the season, which is a positive.
"In Canada, the weather can always play a key role - the forecast currently looks good, but you never know when you pull back the curtains in the morning whether you're going to be faced with blue skies, or grey clouds and pelting rain. We'll probably get a bit of both next week."
Over at Williams, head of performance engineering Rob Smedley says that tyre issues will be a focus throughout the weekend. "Kerbing is also important in Montreal as being able to ride the kerbs over the two chicanes is key to a quick lap time. Our car is aerodynamically efficient which is vital on the long straights in Canada so we feel we are in good shape."
Felipe Massa points out that the top speed of the Mercedes-powered FW36 is good, "which will be our main strength," while team mate Valtteri Bottas has fond memories of the track after qualifying a brilliant third - his best grid position to date - for last year's race.
Elsewhere, Marussia are seeking to build on their Monaco breakthrough, and will be looking to get ahead of Sauber - who could struggle given Montreal's heavy braking zones. Marussia's John Booth says: "As you might imagine, we head to Canada with a definite spring in our step after achieving our first points finish in Monaco. It was an important milestone for everyone in the team and provides an important affirmation, internally and externally, of the positive trajectory we are taking in pursuit of our longer term ambitions.
"Canada is one of our favourite racing destinations, although not necessarily a track that has suited us in the past. It will be interesting to see how well the set-up developments that worked so well for us in Spain and Monaco will translate to the Circuit Gilles Villeneuve. While we are not expecting to replicate our success in Monaco, we are hopeful that we can further underline our recent performance increment with another strong race for both drivers."
At Caterham, American Alexander Rossi will have his first Friday practice outing of the season, which will be a valuable opportunity to offset his difficult start to the GP2 series.
"After the amount of laps I've done in the simulator with CT05 I'm already pretty familiar with how it'll be inside the cockpit," he says. "Obviously it's not quite the same as actually being out on track, but I have a lot of F1 mileage under my belt with the various FP1s and test days I've completed and having driven in FP1 in Canada last year I know I can go straight to work and help the team complete its plan for the session."
Pirelli are providing the teams with the same tyre options they took to Monaco at this race - the yellow-marked softs and the red-marked supersofts. Montreal, however, is very different to Monaco, and the average lap speeds are much higher. It has a low-grip surface, some high kerbs, several big traction zones and a number of big braking events which place very high demands on the brakes.
Paul Hembery, Pirelli motorsport director, says: "We're expecting the tyres to be worked a lot harder in Canada than they were in Monaco, with a lot more energy and greater forces going through them due to much higher speeds. This should lead to the maximum possible mechanical grip, which is certainly what's needed in Montreal.
“There's a high degree of track evolution and we frequently see a lot of sliding - especially with reduced downforce this year - which obviously puts an increased amount of stress on the tyre. But we are still expecting to have contained wear and degradation this weekend, even on the two softest tyres in the range.
"Canada always tends to be an unpredictable race where strategy can make a real difference, also because of the high probability of safety cars. As we saw in Monaco, taking the right strategy opportunities when they present themselves under unusual circumstances is a key element to success at any circuit that falls outside the usual mould, with Canada being a prime example. Historically, there's a reasonable chance of rain, in which case judging the crossover points - sometimes without previous data, if each previous session has been dry - becomes crucial."
Weather forecasts suggest the possibility of showers on Friday, with dry weather and ambient temperatures in the range of 27 to 28 degrees Celsius on Saturday and Sunday.
The track is virtually the same as last year with the only changes being in the positioning of barriers and the removal of the gravel trap in favour of asphalt at Turns 10 and 13. Two DRS zones will again be used, both using a single detection zone located 110 metres after Turn 9. The first zone begins 55m before Turn 12, while the second is activated 70m after the final chicane.
Sunday's race will run over 70 laps or 305.270 kilometres (189.686 miles) and starts at 1400 hours local time, which is four hours behind GMT.