What do you consider as a good slice and which slice is best for which shot/game situation?
I am recently improving my slice technique and found out, that looking into details, there are many variations of slices in terms of spin you can give the ball.
My slice often lacks side spin and my shots are more like too long drop shots, which still sometimes give my opponents a hard time because their trajectory after bouncing is not predictable. But I am focus on giving my balls more sidespin when needed.
Give your statement to this topic please!
First of all, you can only put significant sidespin along with your underspin if the ball is below mid-thigh level, so you can hit it with a sideways swing trajectory. You can't do that when the ball is waist to shoulder height. Above shoulder height, it's possible to put some sidespin rotating the other way if you hit with an inside-out swing above shoulder level, kind of like a mirror image of a slice serve swing.
But the most important thing to think about first is what you are hoping to do or get with the shot your opponent hits against your underspin, and what their tendencies and capabilities are. What you are trying to accomplish often dictates how you approach hitting an underspin.
For instance, I will pretty much win 80% of the points where I get a mid-court forehand that I have time to set up and hit. So depending on my opponent, I'll use underspin not to cause an error, but to disrupt their timing enough so they cough up a short ball I can attack. I can do this by either hitting deep with topspin and then hitting shorter with underspin so they have to move forward, but not have my shot be so short they feel they can effectively come to the net. Then, my next shot will hopefully catch them moving backwards, and I'll be in a favorable position.
If I'm playing someone who's not that quick around the court and I get a short ball to my backhand, I like using a short, sidespin/underspin down the line that bounces twice at about the baseline. These shots are difficult to hit down the line so I prepare myself for a mid-court ball that I hit deep to the opposite corner to attack.
If I am playing someone who has a weaker backhand that can't generate a lot of pace, I'll try to float slow, deep, underspin shots to that side knowing that they can't effectively attack me with no pace on the ball and that eventually, I should get a shorter ball that I can attack.
These are just a few of many variations of things you can do, but like any shot it should be done with a purpose. Figuring out what that purpose is should be the first step if you already think you have some mastery over that shot.