Barcelona moved to within one point of its third straight Spanish league title by beating Espanyol 2-0 in Sunday's Catalan capital derby.
Barcelona can clinch its 21st title with at least a draw at Levante on Wednesday. It leads second-place Real Madrid by eight points and holds the head-to-head advantage with three rounds to play.
"We will now go to Valencia to earn (the title)," Iniesta said. "The important thing is to win another league (crown)."
Wrapping up the domestic competition early would also give Barcelona extra time to prepare for the Champions League final against Manchester United on May 28.
Later, Osasuna looks for a win at Zaragoza in its fight to avoid relegation.
Barcelona coach Pep Guardiola only rested Carles Puyol despite his team coming off a grueling four-game series against Madrid that ended in the Catalan club eliminating its fierce rivals from the Champions League semifinals on Tuesday.
Without shining, Barcelona controlled possession throughout in an unusually subdued match between the crosstown rivals.
Barcelona forward Pedro Rodriguez tested goalkeeper Carlos Kameni with a shot in the 20th, and moments later Kameni dove to deflect a dipping strike from Iniesta.
Espanyol winger Jose Callejon broke free on right side in the 24th, and the Barcelona defense scrambled to clear his low cross for striker Pablo Osvaldo in the box.
Iniesta's goal was an individual effort as he cut back to shake his defender and shot past Kameni with a low right-footer.
Pique put the result beyond doubt when he beat his marker to reach Xavi Hernandez's corner at the near post.
"We tried our best but they were able to score," said Kameni, whose team is four points out of the Europa League positions. "It is difficult, but we will try until the end."
Espanyol looked to pull one back and Osvaldo drew a pair saves from goalie Victor Valdes.
Eric Abidal came on Andreu Fontas in the 70th to make his second appearance since recovering from surgery to remove a liver tumor.
Osvaldo chipped wide late after substitute Alvaro Vazquez played the Argentine striker through on the right side.
Elsewhere, fourth-place Villarreal drew 0-0 at Mallorca on Sunday, to close the gap to third-place Valencia to five points.
The games began after a minute's silence in memory of Seve Ballesteros, the Spanish golf great who died on Saturday.