Transfer trains in Padova - is 9 minutes enough?

It's more than enough time and is quite simple. When you arrive, just check the lighted message boards on each track and determine from which your Regionale will depart. The station has a tunnel under the platforms that connects all 4 platforms - and even has elevators so you don't have to use the stairs. When you get to your designated track, check the info board agai. Last time I was in Padova, a EuroCity train was running late and they changed the Regionale to a different track at last minute.

The DB link at Looking Up Train Schedules and Routes Online is suggesting that you change trains at Venezia Mestre station, giving you 17 minutes, at least on several departures I saw. Either station should work, but if you miss the connection, then direct departures from Mestre run every half hour, versus those departing Padova alternate between direct and one additional connection.

Padua is a pretty small station and you won't have any trouble. As soon as you get off your train, head for the stairs (fastest) or lift (slowest) and head down stairs. At the entrance to each platform is a monitor listing the next trains using it. The Regionale trains usually use the two platforms closest to station lobby.

Your Regionale tickets should be transferable to the next train on that line if you are late. Also, remember to validate your Regionale tickets using the time clock on the platform. Really important...

Just make sure you gather your luggage & stand near the train door as the train approaches Padova (You'll see other passengers doing this), this way you can exit the train as soon as it stops.

If you purchased your train ticket online ( Firenze to Bassano Del Grappa), there is no need to validate this type of ticket at the station prior to boarding your train(s).
However, if you purchased your tickets at the station ( from automated machine or ticket counter), you'll only need to validate the Regionale ticket ( Padova to Bassano Del Grappa) prior to boarding, but you can do this prior to boarding the first train ( frecciarossa train in your case), since you may forget while rushing to transfer in Padova.

Enjoy!

Thanks everyone! I purchased online so I will not plan on validating. Wish I new about the transfer in Mestre, but alas I am already booked to Padova. Sounds like it won't be a problem though - thanks again

If you miss the booked regionale to Bassano you can freely board another regionale headed to the same destination and departing within the following 4 hours.

Nine minutes should be enough time in a 4 tracks station, but you have nothing to worry about: just note down the number and the departure hour of the next couples of Regionale trains to Bassano.