It has been made even more difficult by the resurgence of Kendrick, who was optioned to Triple-A Salt Lake early in the season but has been on a tear since being recalled on July 4.
In fact, Kendrick's .388 batting average since July 4 is the highest in the Majors among players with at least 150 plate appearances. And that's why Scioscia has been trying to make room for Kendrick in the lineup recently despite Izturis' career year at the plate, where he has a .294 batting average.
"Obviously, if Howie keeps swinging the bat like this, it's something we'll have to look at," Scioscia said on Monday before his club hosted the Yankees. "We want to get all three guys to get playing time, but if one guy does something like Howie is doing, they'll get more playing time."
All three players bring something different to the table. Kendrick -- with a career .305 batting average -- is the best pure hitter of the three, Aybar -- with his range and arm -- is the best defensively and Izturis -- with his ability to play three infield positions -- is the most versatile.
Earlier in the season, it was Aybar and Izturis who were the regulars in the Angels' infield, as Kendrick struggled at the plate to the tune of a .231 average through June 11.
Kendrick, though, batted .346 in 20 games with the Salt Lake Bees and quickly regained his stroke. Scioscia credited Kendrick, who has a career average of .360 in the Minor Leagues, with fixing a few flaws in his game at the plate.
"I think he was really searching for some things he wasn't going to find in Major League at-bats," Scioscia said. "There are some things where you have to take a half-step back and experiment, and if you try to experiment in the Majors, it can really set you back. In hindsight, it was probably the best thing that could have happened to Howie."
Specifically, Scioscia pointed out that Kendrick had to work on simply swinging at better pitches to get into a better hitter's count.
"I think he got back in tune with some things he did well in Spring Training with plate discipline," Scioscia said. "It's not necessarily with the walks, but with the pitches he was swinging at by giving counts back to the pitchers, so instead of 2-1, it's 1-2. It's a subtle thing that can create a huge swing there."
It's a similar situation for Kendry Morales right now, as the switch-hitting first baseman is batting just .188 this month after hitting .385 in August.
"He's expanded the zone too much, so he's trying to do some things with pitches that maybe nobody but Vlad can do," Scioscia said of Morales, who was given Monday off. "He just needs to get back in tune with what pitchers are doing."