Spanish teenager Jodar was leading 6-5 in the opening set when thick clouds of smoke drifted onto the centre court from the Stadio Olimpico, where Inter Milan beat Lazio 2-0 in the Coppa Italia soccer final, severely reducing visibility and briefly knocking out the tournament's electronic line-calling system.
Play was halted for almost 20 minutes as officials waited for conditions to improve and for the system to reset.
Television images showed the court shrouded in haze, with players and spectators struggling to follow the action as smoke lingered above the red clay.
Upon return, home favourite Darderi finally ran out a 7-6 (7-5) 5-7 6-0 winner in a three-hour epic that extended his best Masters 1000 run and set up a semi-final showdown with Casper Rudd.
"I think it's the best win of my career because of the crowd and everything here in Rome," the 18th seed, fresh from a statement victory over second seed Alexander Zverev in the previous round, said in his on-court interview.
"First time in the semi-finals, it's a dream to play here. It was difficult because we started around 11, the court was very slow ... I just kept fighting and I'm very happy about that."
Earlier on Wednesday (Thursday AEST), two impressive sets from Ruud saw the Norwegian overcome 13th-ranked Karen Khachanov 6-1 1-6 6-2.
The match was suspended for more than two hours at the start of the second set because of rain and Khachanov seemed to have dealt better with the enforced break.
However, the 23rd-ranked Ruud broke Khachanov's serve twice at the start of the third set and then again to take the match on the second of three match points.
With Reuters.
