Carlos Tevez curled a free-kick over the Roma wall for his 15th league goal of the season that took him top of the Serie A scoring charts. But Malian veteran Keita equalized in the 78th minute as Roma set club record sixth straight home draw.
Roma welcomed the Bianconeri to the Stadio Olimpico desperate for the win that would maintain their unlikely title challenge.
Rudi Garcia's men had drawn six of their last seven league games but had never drawn six times consecutively at home, until Monday.
Under the circumstances, Roma - who have been ravaged by injuries to key players and only recently welcomed back Ivorian striker Gervinho from the Africa Cup of Nations - would be happy with a point.
Garcia told Sky Sport: his side had shown "character" to fight back into the game. "In games like this we know it can come down to dead ball situations and in fact that's how both goals were scored.
"We were down to ten men and a goal down so to come back into the game like we did in those circumstances showed character."
However Juventus remain unbeaten against Roma this season and with a nine-point advantage look to have one hand on what would be a fourth consecutive title.
Coach Massimiliano Allegri said his side had "taken a step forward," but told Sky Sport "The season is still long."
He added: "We played well up until 70 minutes and then we stopped playing. We need to keep our concentration for the entire game."
Roma started with influential midfielders Radja Nainggolan and Juan Iturbe on the bench while Juventus were without Andrea Pirlo and Paul Pogba - two of their most creative players - as they sought to make it two wins from two over the Giallorossi following a bad-tempered 3-2 win in Turin early in the campaign.
After an insipid first half without clear-cut chances, the hosts suffered a blow just after the hour when Vasilis Torosidis saw red for a second bookable offence.
In the absence of free kick specialist Pirlo, who is out for three weeks with a calf injury, Tevez stepped up shot over the Roma wall with Morgan De Sanctis rooted to the spot.
It sent the Argentine back to the top of the Serie A scorers ahead of compatriot Mauro Icardi, of Inter Milan, who has netted 14 times. Tevez almost had a second minutes later but Kostas Manolas's boot blocked the Argentine's half-volley to the right of goal.
Despite their disadvantage, Roma pressed for the equalizer and almost found the breakthrough when Claudio Marchisio caught the heel of Miralem Pjanic on the left flank.
Alessandro Florenzi, who came on for Adem Ljajic just after Torosidis's sending-off, crossed the ball to Manolas whose glancing header forced Gianluigi Buffon to tip the ball to safety down low.
Roma's insistance finally paid off. Juan Iturbe won a free kick to the right of the area after a solid challenge from Giorgio Chiellini. The Colombian's free kick found Keita at the back post and the Malian's header bounced over the line past the foot of Marchisio.
Iturbe should have done better minutes later when he was set up on the edge of the area but somehow bundled a mishit shot wide.