Because the lats insert at the iliac crest – the top of your pelvic girdle – they play a role in back extension. And when you extend your back, you're almost always tilting the top of your pelvis forward at the same time, exaggerating the arch in your lower back.
A lot of lifters exaggerate back extension when they do seated close-grip rows. That is, they bend forward on the negative and then lean backward on the concentric or lifting part of each rep. This puts unnecessary stress on the lower back, while at the same time taking work away from the upper-back muscles.
But there is a way to combine back extension with a close-grip pull without so much risk to your lumbar spine. It's called the standing compound row.
Put the triangle handle on a high cable pulley, stand a few feet back with your feet shoulder-width apart and knees slightly bent, and bend forward at the hips so your torso and arms create a straight line with the cable.
Straighten your hips as you pull the handle to your lower chest. Because you're standing, your lower back doesn't go into as much flexion as it would if you were bending forward on a seated row.
Standing movements like this are always more functional. In sports, the actions requiring upper-body strength and power are almost always dependent on coordinated action with the core and lower body.