So, I've created a "sumo" monk who has the Grappler feat, and is now level 5 and has the Extra Attack class feature. Since I'd like to use one of these attacks to grapple the target, can I use my other attack to punch the grappled target, then use Martial Arts to punch him again?
When you want to grab a creature or wrestle with it, you can use the Attack action to make a special melee attack, a grapple. If you're able to make multiple attacks with the Attack action, this attack replaces one of them.
When you use the Attack action with an unarmed strike or a monk weapon on your turn, you can make one unarmed strike as a bonus action.
Specifically, the wording of Martial Arts doesn't really take Extra Attack into account, since you could make one of those attacks with a monk weapon and or unarmed strike, then draw a longsword and make the other attack with that (or in my case, grapple). I know that Martial Arts does also say "while you are unarmed or wielding only monk weapons", which the longsword example would contradict, but my grapple example doesn't, since I'm still not wielding any weapons or wearing armour/shield.
So my question is Is Martial Arts triggered if only one of the two attacks is an unarmed strike or monk weapon attack (with the other being a grapple), or do both of them have to be unarmed strikes/monk weapon attacks?