Darvish ended his lengthy winless streak his last time out and will look to continue dominating the Astros on Saturday night.
Texas (50-36) won Friday's opener of this three-game set 10-5 and has not lost to Houston (31-56) since an 8-2 defeat March 31 in the Astros' first game as an AL club.
Darvish (8-3, 2.78 ERA) fell one out short of a perfect game in the next meeting, a 14-strikeout performance in a 7-0 victory April 2 that started the Rangers' run over the Astros. He followed that up by yielding three runs and three hits over seven innings to earn an 8-7 win over Houston on May 11.
The right-hander is limiting opponents to an AL-best .190 average, and Houston is hitting .078 against him this year. Darvish gave up two runs over eight innings of a 6-2 home win over Houston last June 15, and he's struck out 33 Astros in 23 2-3 career innings.
"We're comfortable now, I think, with the way he likes to pitch and the way he goes about attacking hitters," Castro told the team's official website. "We kind of learned and made some adjustments based on that first time we saw him."
Astros third baseman Matt Dominguez became the only player to homer twice against Darvish in one game in May.
Houston has struck out a major league-high 808 times, while Darvish leads baseball with 151.
Darvish had been 0-2 with a 2.93 ERA in seven starts before pitching 6 2-3 scoreless innings to earn a 3-2 victory over Cincinnati on Sunday. The Rangers had dropped his previous four outings.
"As a starter, if the team doesn't win the day that you pitch, that can be really frustrated, so that was my thing," Darvish said through his translator.
Cruz has a 12-game hitting streak against the Astros, going 17 for 50 (.340) with 16 RBIs. He's homered in the last three meetings.
The Astros outhit the Rangers 10-9 in the series opener but went 5 for 17 with runners in scoring position in their seventh loss in eight games.
"The effort and focus is definitely there," Astros manager Bo Porter said. "That goes without question with these guys. It's one of those things we've played good teams that have played well and we have not played our best baseball."
Texas is 16-10 against left-handed starters as it faces Dallas Keuchel (4-5, 4.65), who is 0-0 with a 2.45 ERA in two career starts versus the Rangers.
Cruz is the only Rangers player to homer against Keuchel, who owns a 3.03 road ERA compared to 5.62 at home.