Valera shot a 5-under 67 and Rodiles had a 3-under 69 to reach 12-under-par 132 heading into the weekend.
Drysdale followed up his course record-tying 62 on Thursday with a 2-under 70 at Le Meridian Moscow Country Club, allowing the Scotsman to retain at least a share of the lead.
The trio leads by one shot over Alejandro Canizares, also from Spain, who carded a 5-under 67 to stand alone in fourth place at 11-under 133.
South Africa's James Kingston shot a 69 and is fifth at 10-under 134, one shot ahead of four players who share sixth place, including defending champion Mikael Lundberg of Sweden and the player he beat in a playoff last year, Englishman Andrew Butterfield.
Among the co-leaders, Rodiles had the best chance to take the lead by himself, but he bogeyed his final two holes after playing the first 16 at 5-under.
'I am hitting the ball well,' said Rodiles, 'but the thing is that when you are playing that well you should not be giving so many shots away. I made three bogeys today and at least two of them should not have happened.'
Valera played steadily and collected six birdies with just one bogey. He has his sights set on trumping his best-ever finish on the European Tour -- seventh place at the Deutsche Bank TPC Open, a full 10 years ago.
'I had a lot more hair then,' Valera joked. 'It feels great to be back in this position. I just have to keep going and keep learning because you never stop learning in this game.'
As for Drysdale, he failed to capture the magic that brought him his 62 on Thursday. Not that there's too many players around who can accomplish such a feat, as he knows.
'Unless your name is Tiger Woods, it is quite difficult to do that,' admitted Drysdale, who had four birdies and two bogeys Friday. 'I think I'm disappointed because I know this golf course so well and today's round felt worse than it actually was.'
Lundberg and Butterfield shot matching 67s in the second round. Looking to become the first repeat champion ever at this event, Lundberg had six birdies and one bogey Friday.
'I feel like I can't shoot over par around this golf course, which is a great feeling to have,' he said. 'I just wish I felt like that every week. I don't know why that is -- if I knew what it was, then I would take it every week.'
Joining Lundberg and Butterfield at minus-9 were Sweden's Fredrik Andersson (69) and Ireland's Gary Murphy (68).
The cut line fell at 1-under with 74 players in a field of 111 moving on to the weekend.