When an umpire sees the ball thrown more into a player you have to determine if it was a catch for an out or babbled ball that was not got for an out.

Let's cover two basic situations through the first baseman:  the ball is thrown to the first baseman who deflects it off his glove and its hits him in the chest then he folded his arms in and holds a firm against his body. Is that a catch or no catch?

No catch a ball must be held firmly in control and either the glove or in the and no parts of his body can be used to secure the ball or be considered a catch. Another dumb example which I've never seen would be if they trapped it between their legs it would be no catch must be with her hands.

A fly ball to the outfielder: the fielder has the ball into his hand as he runs and/or dives for the ball then even though he takes a few steps and falls down or as the ball popped out of his glove is this a catch or no catch?  It's no catch until they secure the ball firmly enough to go on to the next natural act of the game. Catching a ball in the outfield normally consists of securing the ball in the glove and then taking it out and throwing it back to the infield. Therefore outfielder must secure the ball enough to show the ball, be able to do next movement which is turn to throw, to get out the glove to throw, reason to show the secure, stop running and change directions all the acts natural to the game after controlling the ball can't be babbling the ball as he runs regardless how far he runs.

All these rules apply to catches like any fielder infielder or outfielder having to do the next act natural to the game after securing the ball to have it be called the catch.