San Francisco Giants 3, Dodgers 2.

Paco Rodriguez

Paco Rodriguez has taken the loss in two of his last four appearances. (John McCoy/Staff photographer)

After 159 games, one of the most burning questions facing the Dodgers is this: What should be done with Paco Rodriguez and Edinson Volquez?

Rodriguez entered spring training as a question mark for the 25-man roster. He entered September as the team’s most reliable set-up man. But there was always the lingering question about his workload as a 22-year-old rookie. Thursday’s appearance was his 75th of the season, and while his innings count isn’t appreciably different from last year, the Dodgers made a conscious effort to give him more rest.

So Rodriguez didn’t pitch between last Wednesday and Thursday night, and his location was no different than the last time anyone saw him on a mound — that is, not good.

In the eighth inning of a 2-2 game, Rodriguez served up a line drive to Angel Pagan on an 0-2 slider at the belt. Since this is AT&T Park, a line drive to the left-field corner has the potential to clear the fence. This one didn’t — it bounced off the top of the fence, then over — but it made all the difference in the Dodgers’ 3-2 loss.

Rodriguez has faced 30 batters in September. Fourteen have reached base, six via walk and eight via hit. Three of those eight hits have left the ballpark. His time to dethrone Brian Wilson as the Dodgers’ primary eighth-inning option is basically up. Even if Rodriguez does pitch well in, say, two of the Dodgers’ three games against the Colorado Rockies, how much confidence would that inspire for October?

The problem is the opposite with Volquez. He wasn’t expected to do anything for anyone when the San Diego Padres placed him on unconditional release waivers in August. Not only did the Dodgers snap him up right away, they watched Volquez become their fourth-best starting pitcher. (“Watched” might be accurate, but is far too passive a term here. Volquez and pitching coach Rick Honeycutt watched a lot of video to identify flaws in Volquez’s delivery, but implementing them in such short order, with so much success, could not have been easy.)

Volquez’s 3.52 earned-run average over his last four starts is far better than that of Ricky Nolasco (8.20 in his last four, 12.75 in his last three). Against the Giants, in his final start of the season, Volquez pitched five innings and allowed two runs, both in the fifth inning.

This is a good problem to have. Volquez has at least made it difficult for the Dodgers to leave him off their playoff roster. At most, he has pitched his way into the Game 4 starter’s job, with a big ugly assist from Nolasco.

There are two distinct, glass-half-empty/glass-half-full ways of viewing this.

Half empty: Nolasco and Rodriguez, two pitchers the Dodgers could count on three short weeks ago, are pitching themselves out of October jobs.

Half full: Volquez and Wilson, two pitchers who were not on the Dodgers’ roster in mid-August, have auditioned well. Their roles are important but not major, and the major roles are secure. The projected starters for Games 1, 2 and 3 are enviably stable. The ninth inning is in the seemingly sure hands of Kenley Jansen. The Dodgers’ burning questions are on the back burner.

Chris Withrow threw two scoreless innings Thursday. If the season ended today, he and Wilson would be the team’s top right-handed set-up men, J.P. Howell the top lefty, and Volquez might be the Game 4 starter.

Scary thing is, the season ends in three days. It’s unexpected, maybe a little weird, but hey — it might work.

Some bullet points:

• The box score is here.

Juan Uribe‘s ground-rule double in the fourth inning might have been the first ball ever to angle sideways off one wall and land over another wall for a ground-rule double.

• After the game, Wilson walked over to the front-row seat of his former boss, San Francisco Giants President and CEO Larry Baer. They had a short conversation and Wilson didn’t appear to be in a good mood. Wilson might have been angry about some jewelry.