It was cold, it was wet and it was gray. All in all, a pretty miserable day on the banks of the Ohio River. And yet, it was everything the Mets envisioned: an effective start from Johan Santana, just enough offense to give them the lead and a dominant performance by their overhauled bullpen.Santana allowed just one run in 5 2/3 innings, Daniel Murphy drove in two runs and Francisco Rodriguez got his first save in a Mets uniform in a 2-1 victory Monday over the Cincinnati Reds.