Adam Weinrib is joined by guest host Sam Phalen (filling in for Robert Murray) to break down the biggest MLB storylines as we enter the stretch run of the season:

Which contenders made the most of their roster shuffles before September?

The September call-ups to watch: Tong, Nolan McLean, Basallo, and more.

Which veterans on new teams (Walker Buehler to PHI, Andrew Heaney to LAD, IKF to TOR, Carlos Santana to CHC) could actually make an impact?

Are the AL & NL playoff fields locked in — or still vulnerable?

Which non-contenders could play spoiler down the stretch?