Kevin Jurovich caught 10 passes for 161 yards to become the first Spartans receiver with back-to-back games of 100 receiving yards or more in five years.
Callier helped San Jose State (3-3, 2-0 in the WAC) re-establish its running game, going for 93 yards on 31 carries as the Spartans recorded their first 100-yard rushing game of the year. Tafralis finished with 302 yards on 22-of-30 passing.
WAC rushing leader Deonte Jackson, slowed by a sprained ankle, gained 94 yards on 22 carries for Idaho (1-5, 0-2 WAC), which lost its fourth straight. Bryan Flowers added 86 yards on 10 carries.
Idaho piled up 141 of its 251 yards in the first quarter alone, and held onto the ball for nearly 10 minutes. Tino Amancio's 34-yard field goal with 4:31 left in the period, though, was all the Vandals had to show for it.
San Jose State scored two minutes later and never trailed again.
Amancio connected on a 27-yard attempt early in the second quarter to bring Idaho within 7-6, but the Spartans put together two 80-yard scoring drives in the final 5:13 of the first half and took a 21-6 lead into the intermission.
The Spartans failed to convert on a fourth down pass play in Idaho territory, which ended their first drive.
San Jose State's David Marrero, a running back at Stanford two years ago, returned a kickoff 21 yards to the Spartans' 39-yard line and Tafralis found David Richmond to complete a 48-yard pass that led to San Jose State's first rushing touchdown of the season -- a two-yard run by Callier. He also ran in from one-yard out with 5:13 left in the second quarter.
Tafralis found a wide open Jurovich for a 33-yard touchdown with 33 seconds left in the first half.
The Spartans tacked on another touchdown early in the fourth quarter on Tafralis' 13-yard pass to Jeff Clark to make it 28-6.
That's when the ball began bouncing into the Vandals' hands. Maurice Shaw recovered a blocked punt in the end zone to bring Idaho within 28-13 with just under 10 minutes to play. Joseph Dickson rushed in untouched to get his hands on the ball.
Eric Hunter picked off a Tafralis pass seconds later, setting up a 19-yard run by Flowers, Jr.
The Vandals got the ball back with just over two minutes left but Jonathan Harris intercepted a Nooy pass to secure it.
Idaho lost its fifth straight on the road, and fifth of six overall to the Spartans.
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