Tendulkar, 35, surpassed West Indian Brian Lara's tally of 11,953 runs to become the highest run-getter in Test cricket and overshadow everything else that happened on the field.
He reached the landmark in the first over after tea when he steered debutant paceman Peter Siddle past third-man for three runs to move past 15, sending the 15,000 crowd at the Punjab Cricket Association stadium into a frenzy.
Tendulkar (88) looked in ominous form as he cut, pulled and drove in exquisite fashion to reach his 50th Test half-century and complete an incredible 12,000 runs in the process.
His 111-ball knock, containing 10 fours, was cut short by Siddle when he edged him to Matthew Hayden who took a fine low catch at first slip.
Ganguly, batting on 54 at close with four fours, also achieved a personal milestone when he reached 39, becoming the fourth Indian to score 7,000 runs behind Sunil Gavaskar, Tendulkar and Rahul Dravid.
The 142-run stand between Tendulkar and Ganguly lifted the Indians, who were placed at a shaky 174-4 after Australian paceman Mitchell Johnson (3-68) picked two key wickets in the post-lunch session.
The 26-year-old left-arm quick sent back opener Gautam Gambhir (67) and the stylish Venkatsai Laxman (12) after having got rid of the dangerous Virender Sehwag (35) in the opening session.
But it was paceman Brett Lee (1-56) who gave his team the much-needed breakthrough by breaking the 76-run second-wicket stand between Gambhir and Dravid (39).
Lee, who had looked quite off-colour earlier, tempted Dravid to go for an expansive drive but the batsman ended up inside edging on to his leg-stump.
It was the 291st wicket for Lee, who becomes the fourth highest Australian wicket-taker ever.
Johnson then forced an edge from Gambhir as he tried to drive a full delivery through the covers before dismissing Laxman by having him caught down the legside.
The three quick dismissals in the space of 17 runs turned the tide in favour of Australia, looking to go 1-0 up in the four-Test series for the Border-Gavaskar trophy after the drawn Bangalore opener.
Earlier Sehwag and Gambhir belted a wayward Australian attack after Mahendra Dhoni won the toss and elected to bat in the absence of injured regular captain Anil Kumble.
Kumble, who turned 38 on Friday, pulled out of the Test on the morning of the match after failing to recover from a shoulder injury.
The explosive Sehwag, who hit Siddle for two fours in an over, appeared in top form during his quickfire knock, which came off 36 balls.
Gambhir joined in the run-fest, reaching his seventh Test fifty and first against Australia by lofting part-time spinner Michael Clarke for two fours on the trot over long-on.
Australia awarded a Test cap to Siddle after paceman Stuart Clark was ruled unfit for the match.
India blooded leg-spinner Amit Mishra, who featured in three one-day internationals for India way back in 2003.