After reading thru the play-by-play, it looks like 1 ER to me. MAYBE 2 ERs at the most (it does get confusing sometimes).

Ojeda's homer in the 8th is obvious. (That name sounds familiar )

But the 4th inning is such:

SAN DIEGO 4TH
-F Guzman flied out to center.
-M Loretta safe at third on throwing error by shortstop J Gil.
-R Aurilia singled to center, M Loretta scored.
-P Nevin singled to left, R Aurilia to second.
-M Ojeda grounded into fielder's choice to third, P Nevin out at second, R Aurilia to third.
-X Nady reached on infield single to third, R Aurilia scored, M Ojeda to second.
-J Payton singled to right, M Ojeda scored, X Nady to third.
-A Gonzalez tripled to deep right center, X Nady and J Payton scored.
-B Sweeney grounded out to third.

5 runs, 5 hits, 1 error
San Diego 5, Arizona 0

TO ME, that was a terrible inning. While, personally, I see the first run being unearned; I wouldn't be all that surprised if they rule the subsequent runs earned after all those hits.

We'll see for sure tomorrow. But yeah, FS sounds right (for once)