Something that always bothers me in my writing is how often I start sentences with the word "the".
A terrible nonsensical example:
The dog ran through the rain-swept streets, chasing a ball he thought he'd lost. The ball was just ahead of him, always out of reach. The ball was a dull red colour, difficult to see through the rain. The dog was gaining on it, slowly but surely.
Note: this isn't an extract of something I've written but a quick sample to demonstrate the problem. Answers that only deal with restructuring this particular paragraph are not useful.
I'm not concerned with the quality of my writing overall. I know that's something that will improve with time and practice. This also isn't about overuse of "the" in general, which would be a duplicate of this question.
What techniques can I use to prevent myself from starting sentences with "the"?