The Argentine goalkeeper produced a sensational save to deny Alessandro Florenzi in the closing minutes after both sides had squandered clear chances to snatch all three points
The Argentine denied Alessandro Florenzi from close range in stunning style in the final 10 minutes after Gervinho and Stefano Okaka had earlier spurned glorious chances as Rudi Garcia's men failed to bounce back from their humiliation at the hands of Bayern Munich with a win.
The result means Roma remain second in Serie A, now level on points with leaders Juventus having played a game more. Third-place Sampdoria remain undefeated after eight league matches.
Morgan De Sanctis was called into action in the first few minutes as he saved Roberto Soriano's close-range effort at the near post.
Opportunities to score were few and far between in the early stages, with Francesco Totti firing over from inside the area and Florenzi hitting a tame effort towards goal from 20 yards as Roma carved out half-chances.
Gervinho spurned the first clear-cut chance, racing clear from Totti's through ball before fortuitously rounding the keeper, but he could only play the ball against the post from a tight angle.
Gervinho fired just wide a matter of moments later and came closest at the start of the second half, too, as he forced Romero into an excellent stop at full stretch after another bold run forward.
Sampdoria then had a penalty appeal turned down as Eder was blocked by Astori, before Roma became incensed that the Brazilian was not punished for handball inside his own area at the other end.
The home side then spurned a glorious opening. Jose Holebas scythed down Soriano to earn a booking and concede a free kick far on the right and Okaka met the ensuing cross at the far post but somehow contrived to put the ball over the crossbar with the goal gaping.
Garcia then threw on Miralem Pjanic to attempt to force a breakthrough and the midfielder promptly earned a free kick in a dangerous area, but Roma failed to take advantage.
Roma, who had struggled for 80 minutes to find a rhythm in their passing game, finally strung together an impressive move involving Pjanic, Radja Nainggolan and Vasilis Torosidis, and his cross was met with a powerful header by Florenzi, but Romero was on hand to produce a sensational stop to deny the Giallorossi a victory.