Strung together, tiers of the log

The most consistent team of the previous two IPLs, the Delhi Daredevils, surprised everyone by following the same trend as the Kolkata Knight Riders this season. Both team won their opening two matches and lost their next three, before bouncing back to win their next one. They're now sitting precariously on the brink where a victory will set their path right and a defeat will see a series of up and down results strung together and probably confine them to the bottom tiers of the log.

Could you please explain to me the emboldened parts?