The 49ers need help on both sides of the ball in this year’s draft, but a four-round mock from NFL.com’s Chad Reuter has them using all four of their selections on defensive players. While they have needs on offense, it’s not an outlandish thought that go defense-heavy through the first four rounds. San Francisco has Arik Armstead, Fred Warner and will soon have Nick Bosa making big-time money on that side of the ball. Getting cost-controlled, starting-caliber defenders will be a must for them to continue putting together clubs that can make deep playoff runs. Let’s look at how the four-round mock shakes out for them: