one?? he has pitched well since he has been back up. Can you name anyone better for the 4th-5th spot??
Assuming a top 3 of Znn, Marquis, and Maya then yes, I can think of a handful of better options. They've been listed in other spots already but guys like Livan (if re-signed), Olsen, Detwiler, Chico, Martin, Milone, Solis all should be given a shot and all have either better stuff or better production through the minors than Lannan. If everything goes well for Lannan he's a #5 SP on a winning team. Each of those other guys brings more than that in some form.