Tread close upon synonyms

What is another word for Tread close upon?

• tail
• shadow
• follow
• trail
• pursue
• heel
• go after
• tread on the heels of
• follow in the steps of
• hang on the skirts of
• bring up the rear
• follow in the wake of
• follow on the heels of
• camp on the trail of
• follow in the trail of
• move behind
• go in the rear of
• trail after
• take one's dust
• swallow one's dust