Sir Bradley Wiggins appeared to call time on his Grand Tour career after picking up a silver medal on his track comeback at the Commonwealth Games.
Wiggins, riding just his second major track meeting since the 2008 Beijing Olympics, led Ed Clancy, Steven Burke and Andy Tennant in the team pursuit to finish second for England behind a dominant Australian quartet.
The 2012 Tour de France winner was a controversial omission from Team Sky's squad this year, but had previously indicated willingness to ride at the Vuelta a Espana, a race his rival and fellow Tour winner Chris Froome will now target.
But, speaking moments after laying hands on his fourth Commonwealth silver medal, Wiggins indicated a shift in priorities that could see him focus exclusively on the team pursuit and a fifth Olympic gold.
"I certainly answered the question of whether I can still do it or not but I still think it will take a lot more improvement and a lot more dedication," he said.
"I don't think I'm doing the Vuelta any more now so I think that could be it, yeah.
"I just think with the commitment it will take to ride track and the speeds we will have to go at, I think it will take a complete change.
"You're already looking at changing body composition and things like that - getting heavier and more explosive - which will hinder climbing in Grand Tours. And I don't relish the idea of riding round in the back group for three weeks having won the Tour.
"I think 3minutes 50seconds will probably be the mark (for team pursuit gold at Rio), if you look at the progression of previous Olympic Games, so it's almost going to become a sprint endurance event now. It's completely different and I don't think the (track) will necessarily complement the Grand Tour races."
Anna Meares claimed a record-equalling fifth gold medal, riding to victory in the women's 500m time trial.
The Olympic champion led an Australian one-two, clocking 33:435 to secure victory ahead of Stephanie Morton (34:079) and England's Jess Varnish (34:267).
Meares' triumph saw her join compatriot Bradley McGee on a record five gold medals in track cycling, and made her the first athlete to win a medal in track cycling at four different Games.
Ross Murdoch read Michael Jamieson's lines to take Commonwealth gold in the men's 200 metres breaststroke final.
The stage had long been set for Glasgow swimmer Jamieson to top the podium in his home city, but when he was shaded by compatriot Murdoch in the heats, it looked as though the pair had been cast in the wrong roles.
And so it proved in the final showdown as Dumbarton swimmer Murdoch touched the wall first with a brilliant Games record of two minutes 07.30 seconds.
Jamieson took second and England's Andrew Willis third.
Edinburgh judoka Kimberley Renicks won gold for Scotland in the women's under-48kgs Commonwealth Games final with victory over India's Sushila Likmabam.
Renicks, scored an ippon throw to the delight of the partisan crowd at the SECC venue, as the hosts landed their first gold at Glasgow 2014.
Louise Renicks completed the family double with victory over Kelly Edwards in the under-52kgs final, with the English fighter disqualified after collecting four penalties.
Both women were cautioned by the referee for various infringements, which now include leaving the yellow combat zone.
There were just three seconds left of regulation time when Edwards picked up a fourth shido, for a false attack, handing gold to the Scot.
Ashley McKenzie won gold for England in the under-60kgs with a shido penalty victory over Navjot Chana after an edgy contest.
The Indian had gone ahead with a 10-point waza-ari score, only for McKenzie to quickly go on the offensive and the Londoner thought he had won the contest with a hip throw, given as ippon, but then downgraded after a lengthy review.
Eventually the scoreboard was reset, and McKenzie kept his cool to close out victory as Chana racked up three penalty scores.
Colin Oates also captured gold for England at under-66kgs when he defeated Andreas Krassas of Cyprus with a quick throw and armlock combination.
Oates, brought up in Norfolk, but now fighting out of the Edinburgh Ratho club, had reached the Olympic quarter-finals, since when he has steadily climbed the world rankings.
The 31-year-old produced some strong Ne Waza groundwork en route to the final, and followed that up with another impressive display to continue the home nation domination of the Judo competition.
Gold in the women's under-57kgs went to England's Nekoda Davis, who beat Scot Stephanie Inglis.
Davis, based at British Judo's Centre of Excellence in Walsall, scored a Waza-ari throw, which she followed up with a 25-seconds hold-down to clinch the title.
Hannah Miley had the Saltire flying high on the opening night of the Commonwealth Games swimming at Tollcross as she successfully defended her 400 metres individual medley title.
Miley pipped English rival Aimee Willmott to the wall - making her victory an even more popular one - in a Games-record time of four minutes and 31.76 seconds.