Pft, I'm at a loss here. Realistically, Jiren should easily tank anything he can dish out, but if this scenario actually occurred in RaM, I'm sure Rick would come up with some kind of way to take out Jiren here.
Of course, if bloodlusted, Jiren could always kill Rick as soon as the fight starts, before any synapses come close to firing in his brain, but I'm pretty sure that's not what this thread is asking.
He would have to conjure something that would either make him invincible/untouchable, and be able to kill Jiren, or something that would stop him from moving whatsoever.
His traditional arsenal would do nothing to Jiren, however. Unless he gets to activate something before the fight starts, Jiren could potentially kill him before he can even think to move. Even if he had an anti-matter gun pointed at Jiren(assuming that could even kill Jiren) with his finger on the trigger, Jiren would have him vaporized before that finger ever get any closer to firing.