Open up the top and the side facing the player, revealing the hammers, and throw a u47 over it. Position it according to the range the pianist is using and the amount of room ambience you're looking for.
You can also try using a stereo mic if you need the imaging; I recently had great luck with an sf24.
The other approach I use is mic'ing the back of the piano. There's usually a pretty distinct place on the soundboard where you can really hear the sound "happening"; find it and point a mic at it. On my piano, it's most often near the lower-right corner, about 2/3s of the way to the right (if you're facing the back of the piano; in other words, the mic is pointed at the side with the bass strings) and 2/3s of the way down. My go-to mic here is a Gefell umt70s.
On a recent session, where I needed a wide variety of piano sounds, I used all three set ups. The two "overheads" were placed in the same spot, so they were in-phase, and as it turned out, adding in the soundboard mic sounded great, so on a few of the tunes I was using all four mics. Crazy stuff; you never know what's gonna work!!