SAN FRANCISCO The Giants have a lot of holes on their roster, but theres one area where the needs are particularly glaring.At the moment, there is one outfielder, Steven Duggar, who looks like a solid bet to be a starter on Opening Day, but even he faces question marks after having his rookie season cut short by shoulder surgery. Farhan Zaidi needs a couple of solutions for the corner spots, and depending on what he does with the arbitration-eligible Gorkys Hernandez, he may need another player capable of handling center.